This is a Technical Report Summary (TRS) for Walker Lane Minerals Corporation (WLMC), an indirect, wholly-owned subsidiary of Fortitude Gold Corporation (FGC), on its 100%-controlled Isabella Pearl mine, a producing open pit gold-silver heap leach operation in Mineral County, Nevada. The report was prepared by Qualified Persons, under the direction of Ralston Pedersen, P.E., President & Director, Convergent Mining, LLC, Independent (Convergent) and provides a summary of the detailed assessments of mineral resources and mineral reserves and other relevant considerations of the Isabella Pearl mine.

On October 31, 2018, the SEC announced that it was adopting amendments to modernize the property disclosure requirements for mining registrants, and related guidance, under the Securities Act of 1933 and the Securities Exchange Act of 1934 (SEC, 2018 a, b). This report is prepared to comply with the new rule (17 CFR subpart 229.1300), requiring that a registrant with material mining operations must disclose specified information in Securities Act and Exchange Act filings concerning its mineral resources, in addition to its mineral reserves.

WLMC has received all regulatory permit approvals from the Nevada Division of Environmental Protection (NDEP) and the U.S. Department of the Interior, Bureau of Land Management (BLM) for the Isabella Pearl mine. Construction of the Isabella Pearl mine was completed during 2019 and reached commercial production levels in October 2019.

1.1	Property Summary and Ownership

1.1.1

Property Description

The Isabella Pearl mine area covers approximately 627 hectares (1,549 acres) and consists of 90 unpatented lode mineral claims on land owned by the U.S. government and administered by the BLM. WLMC controls 100% interest in the Isabella Pearl claims which are subject to a 2.75% NSR royalty.

WLMC also controls an additional 478 unpatented claims covering approximately 3,329 hectares (8,227 acres) along a nearly 26 km (16 mi) trend extending northwest of the Isabella Pearl mine.

1.2	Mineral Resource Statement

As part of its modernization of the property disclosure requirements for mining registrants, the SEC is adopting the Combined Reserves International Reporting Standards Committee (CRIRSCO) framework for reporting mineral resources. According to CRIRSCO, a mineral resource is a concentration or occurrence of material of intrinsic economic interest in or on the Earth’s crust (a deposit) in such form, grade or quality, and quantity that there are reasonable prospects for eventual economic extraction. The location, quantity, grade, geological characteristics, and continuity of a mineral resource are known, estimated, or

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Isabella Pearl Mine S-K 1300 Technical Report Summary

interpreted from specific geological evidence and knowledge. Mineral resources are sub-divided, in order of increasing geological confidence, into Inferred, Indicated and Measured categories. Portions of a deposit that do not have reasonable prospects for eventual economic extraction must not be included in a mineral resource. The modeling and estimation of mineral resources utilized a portion of the drill hole database compiled by WLMC consisting of:

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Air Track (AT): 6 drill holes for 82.0 m (269 ft)

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Reverse Circulation (RC): 554 drill holes for 53,317.2 m (174,925 ft)

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Diamond Drill (Core) Hole (DDH): 36 drill holes for 3,564.4 m (11,695 ft)

Mineral resource modeling was carried out on capped composites using Inverse Distance Cubed (“ID3”), Ordinary Kriging (“OK”) and Nearest Neighbor (“NN”) estimation methods. A minimum of three and a maximum of twelve composites were used for estimation, within a search ellipsoid oriented parallel with each defined structure and extending 120 m (394 ft) x 120 m (394 ft) x 30 m (98 ft). The major and semi-major axes approximate the average strike and dip directions of the mineralization in each of the estimation areas. Both gold and silver were estimated.

Mineral resources at Isabella Pearl are further defined by WLMC as mineral resources within a constraining pit shell and above a defined cut-off value. The mineral resources reported herein have been constrained within a Lerchs-Grossman (LG) optimized pit shell and reported at a cut-off grade of 0.33 g/t Au (0.01 opst Au) for oxide mineral resources and 2.00 g/t Au (0.058 opst Au) for sulfide mineral resources. Mineral resources are reported inclusive of mineral reserves.

Measured and Indicated mineral resources reported for Isabella Pearl contain 924,300 tonnes (1,018,900 short tons) of material at an average gold grade of 3.22 g/t Au (0.094 opst Au) and 37 g/t Ag (1.085 opst Ag) (Table 11). Inferred mineral resources reported for Isabella Pearl contain 130,800 tonnes (144,100 short tons) of material at an average gold grade of 1.37 g/t Au (0.040 opst Au) and 12 g/t Ag (0.354 opst Ag).

Table 1-1 : Mineral Resource Estimates (inclusive of Mineral Reserves) for the Isabella Pearl Deposit, Mineral County, Nevada, as of December 31, 2022

Oxides	Cut-off Au (g/t)	Tonnes	Short Tons	Au (g/t)	Au (opst)	Ag (g/t)	Ag (opst)	Au (oz)	Ag (oz)
Measured	0.33	374,600	412,900	3.75	0.11	50.1	1.461	45,200	603,100
Indicated	0.33	315,000	347,200	1.32	0.04	12.2	0.356	13,400	123,700
Mea+Ind	0.33	689,500	760,100	2.64	0.08	32.8	0.956	58,500	726,800
Inferred	0.33	125,400	138,300	1.26	0.04	11.9	0.347	5,100	47,900

Sulfides	Cut-off Au (g/t)	Tonnes	Short Tons	Au (g/t)	Au (opst)	Ag (g/t)	Ag (opst)	Au (oz)	Ag (oz)
Measured	2.00	158,300	174,500	4.96	0.14	58.8	1.715	25,200	299,300
Indicated	2.00	76,400	84,200	4.81	0.14	32.2	0.940	11,800	79,200
Mea+Ind	2.00	234,800	258,800	3.34	0.10	50.1	1.463	37,100	378,500
Inferred	2.00	5,300	5,900	3.84	0.11	18.4	0.537	700	3,100

Total	Cut-off Au (g/t)	Tonnes	Short Tons	Au (g/t)	Au (opst)	Ag (g/t)	Ag (opst)	Au (oz)	Ag (oz)
Measured	---	532,900	587,400	4.11	0.12	52.7	1.536	70,400	902,400
Indicated	---	391,400	431,400	2.00	0.06	16.1	0.470	25,200	202,900
Mea+Ind	---	924,300	1,018,900	3.22	0.09	37.2	1.085	95,600	1,105,300
Inferred	---	130,800	144,100	1.37	0.04	12.2	0.354	5,800	51,100

Notes:

Reported at a cut-off of 0.33 Au g/t (0.01 Au opst) for oxide mineral resources and 2.00 Au g/t (0.058 Au opst) for sulfide mineral resources.

Whole block diluted estimates reported within an optimized pit shell.

Mineral resources do not have demonstrated economic viability.

Totals may not sum exactly due to rounding.

Mineral resources reported are inclusive of mineral reserves.

1.3	Mineral Reserve Statement

Mineral reserves were prepared according to the guidelines of Regulation S-K Subpart 1300 (“S-K 1300”). The reserve estimate is based on technical data and information available as of December 31, 2022.

The conversion of mineral resources to mineral reserves required accumulative knowledge achieved through LG pit optimization, detailed pit design, scheduling and associated modifying parameters. Detailed access, haulage, and operational cost criteria were applied in this process for the Pearl and Civit Cat North deposits, the currently minable portions of the Isabella Pearl mine. The mine was built in metric units and all metal grades are in g/t.

The orientation, proximity to the topographic surface, and geological controls of the Isabella Pearl mineral reserves support mining with open pit mining techniques. To calculate the mineral reserve, pits were designed following an optimized LG pit based on a $1,750/oz Au sales price. This price was chosen to create the primary guide surface based on a price sensitivity and subsequent profitability study that showed that the $1,750 pit maximized profitability while reducing capital requirements. The quantities of material within the designed pits were calculated using a cut-off grade of 0.33 g/t Au (0.01 opst) which is based on the consensus 2023-2024 average price of $1,750/oz for gold (CIBC, 2023). The Isabella Pearl mine open pit mineral reserve statement is presented in Table 1-2.

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The high-grade and low-grade stockpiles of ore mined but not processed is included in the inventory of 2022 mineral reserves.

Table 1-2 : Mineral Reserve Estimates for the Isabella Pearl Deposit, Mineral County, Nevada, as of December 31, 2022


Class	Tonnes	Short Tons	Au g/t	Au opst	Ag g/t	Ag opst	Au Oz	Ag Oz
Proven Mineral Reserves	250,400	276,000	4.38	0.128	49	1.4	35,200	392,700
Probable Mineral Reserves	171,500	189,100	1.77	0.052	17	0.5	9,800	92,900
Proven and Probable Total	421,900	465,100	3.32	0.097	36	1.0	45,000	485,600
High-Grade Stockpile	65,300	72,000	3.46	0.101	37	1.1	7,300	78,400
Low-Grade Stockpile	426,500	470,100	0.52	0.015	6	0.2	7,100	76,600
Isabella Pearl Mine Total	913,700	1,007,181	2.02	0.059	22	0.6	59,400	640,600

Notes:

Mineral Reserves were estimated by WLMC and reviewed and accepted by Convergent Mining.

Classification of Mineral Reserves is in accordance with the S-K 1300 classification system.

Metal prices used for Proven and Probable reserves were $1,750 per ounce of gold and $21 per ounce of silver. These prices reflect the consensus 2023-2024 average prices for gold and silver (CIBC, 2023).

The quantities of material within the designed pits were calculated using a cut-off grade of 0.33 Au g/t.

Mining, processing, energy, administrative and smelting/refining costs were based on 2022 actual costs for the Isabella Pearl mine.

Metallurgical gold recovery assumptions used were 81% for all ore which is currently being crushed. These recoveries reflect predicted average recoveries from metallurgical test programs.

Proven and Probable reserves are diluted and factored for expected mining recovery.

A bulk density of 2.44 lbs/ft was used for waste. The bulk density of Mineral Reserves was calculated by block, based on mineralogical content.

Figures in tables are rounded to reflect estimate precision and small differences generated by rounding are not material to estimates.

10.

The Qualified Person for the mineral reserve estimate is Mr. Ralston Pedersen, P.E., of Convergent Mining

1.4	Geology and Mineralization

1.4.1

Geologic Setting, Mineralization, and Mineralization

The Isabella Pearl mine is in the central portion of the Walker Lane, a major northwest-trending zone on the western border of Nevada characterized by a series of closely spaced dextral strike-slip faults that were active throughout much of the middle to late Cenozoic. It is a complex zone up to 300 km (186 mi) wide and 1,000 km (620 mi) long that lies on the western boundary of the Basin and Range Province.

Volcanic rocks of middle Tertiary age cover much of the property and include intermediate lava flows and ignimbrite ash flow sheets. The volcanic rocks unconformably overlie Mesozoic strata including Triassic and Jurassic sedimentary units and Cretaceous and Jurassic igneous units. Tectonic activity and erosion have left an irregular, dominantly buried surface of Mesozoic rocks. Within the regional Walker Lane tectonic setting, several major fault zones trend through the property and are dominated by various splays and off set branches. The Soda Springs Valley fault zone is a major host of mineralization in the area, and particularly along the Pearl fault strand.

The gold-silver mineralized zones include the Isabella, Pearl, Civit Cat North, Silica Knob, Scarlet North and South, and Crimson oxide deposits and the Pearl and Civit Cat North sulfide deposits, collectively referred to in this report as the Isabella Pearl deposit. Alteration and mineral assemblages at Isabella Pearl,

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including widespread argillic alteration and generally abundant alunite, indicate the deposits belong to the high-sulfidation class of epithermal mineral deposits. K-Ar age determinations indicate the mineralization is about 19 Ma, some 7 to 10 million years younger than the age of the host rocks. This early Miocene age conforms to the age of other high-sulfidation epithermal precious-metal deposits in the Walker Lane area (e.g., Goldfield and Paradise Peak).

1.4.2

Exploration

Modern exploration of the general area around the Isabella Pearl mine began in the early 1970’s by various companies. From 1987 through 1990, Combined Metals Reduction Company (CMRC) drilled the Isabella Pearl area during its joint venture with Homestake Mining Company (Homestake). The joint venture drilled at least 175 reverse circulation (RC) and diamond drill (core) holes (DDH) before the joint venture was terminated. TXAU Investments, Inc. (TXAU), also known as TXAU Development Ltd. and Isabella Pearl LLC., conducted a DDH drilling program in early 2007 that consisted of 19 holes. This drilling was designed primarily to provide material for metallurgical testing and confirm the historic assay and geological data collected by the CMRC-Homestake joint venture. In 2008, TXAU completed 7 DDH’s in the Pearl deposit to address some issues concerning assays and insufficient quality assurance/quality control measures from prior drilling. From 2016 through 2022, WLMC executed RC and DDH drilling programs to collect representative mineralized ore grade samples in the mine area in sufficient quantity to conduct metallurgical testing and expand resources. In addition, WLMC completed a 5-hole RC condemnation drill program to ensure no mineral resources occurred where the mine/plant facilities are located. The Isabella Pearl mine drilling history is summarized in Table 13.

Table 13 : Drilling History at the Isabella Pearl Mine (1987 - 2022)

Company	Period	RC		DDH (Core)		Total
Company	Period			No.	Meters	No.	Meters	No.	Meters
Combined Metals-Homestake & Historical	1987-1990	182	19,598.6	6	513	188	20,111.6
TXAU	2007-2008	-	-	26	2,315.7	26	2,315.7
WLMC*	2016-2022	394	35,640	5	442.8	399	36,082.8
WLMC Met Holes	2016-2017	-	-	3	659.9	3	659.9
Totals		576	55,238.6	40	3,931.4	616	59,170
*Includes 6 Air Track (AT) drill holes

1.5	Metallurgy and Mineral Processing

Metallurgical test work has validated that Isabella Pearl oxidized ores are amenable to gold and silver recovery by cyanidation. The most economically effective process has been identified as conventional heap leaching of crushed ore, and to a much lesser extent ROM, followed by absorption/desorption recovery (ADR) and refining to produce doré bars.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Cyanidation test work (bottle roll and column leach), performed on representative samples of the mineral resources, confirms the close relationship between particle size and gold recovery. The greater the fines fraction the higher the gold recovery. Based on the metallurgical test work completed, total gold recovery is expected over a four-month period.

Mineral reserves above 0.61 g/t Au are being crushed to a P80 of 5/8 inch and placed directly on the heap. Mineral reserves between 0.33 and 0.61 g/t Au are being stockpiled for either future crushing or blending with the higher-grade material. The total predicted gold recovery for all ore is 81% ore which is currently being crushed. The gold recovery projection for ore is based primarily on column leach test work and partly on benchmarking other heap leach operations.

Over the Life-of-Mine (LOM), ore is delivered from the open pit, the majority being trucked to the crusher, and then transported to the heap leach pad via an overland conveyor and stacked onto the heap leach pad by a radial stacker. A minor amount of ROM ore was previously placed directly on the heap leach pad by truck.

1.6	Mine Design, Optimization and Scheduling

Isabella Pearl is a disseminated gold and silver deposit with mineralization close to the surface at an average head grade of 2.02 g/t Au (0.059 opst) and 22 g/t Ag (0.6 opst). It was determined that mining would be performed with an open pit truck/loader operation. Initial costs were estimated, and a detailed feasibility study analysis performed to determine the optimum ultimate mining limit for the operation. Average operating costs at the property are approximately 2.6 $/t for mining, 2.8 $/t for crushing and 6.9 $/t for leaching and solution treatment at the Isabella Pearl processing facility.

The current mine design consists of one main pit and several smaller sub-pits accessing the Isabella, Pearl and Civit Cat North deposits. Open pit mining is by conventional diesel-powered equipment, utilizing a combination of blasthole drills, wheel loaders, and 91-tonne (100-short ton) trucks to handle ore and waste. Support equipment including of graders, track dozers, and water trucks also aid in the mining. High-grade ore (>0.61 g/t Au; 0.018 opst) is hauled to the crushing area and crushed before being placed on the leach pad. Low-grade ore between 0.33 and 0.61 g/t Au (0.010 opst and 0.018 opst) is hauled directly to the low-grade stockpile. Waste rock is stored in the waste rock facility designed near the pit to reduce haulage costs.

1.7	Environmental Studies, Permitting, and Plans, Negotiations or Agreements with Local Individuals or Groups

The Isabella Pearl mine is located on public lands administered by the U.S. Department of the Interior, BLM. As such, the operation requires the identified federal permits, the most important of which are approvals of the Plan of Operations (POO) and its subsequent National Environmental Policy Act Evaluation (NEPA) analyses. WLMC submitted the POO and Reclamation Permit applications and the Environmental Assessment (EA). The BLM has reviewed baseline data and deemed the POO “complete” and authorized processing of the EA of the operations. The NEPA analysis was completed, and a Record of Decision (ROD) issued on May 15, 2018. (DOI-BLM-NV-C010-2018-0007-EA). Subsequent minor

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Isabella Pearl Mine S-K 1300 Technical Report Summary

modifications have been processed under Determination of NEPA Adequacy (DNA) level analysis since 2018.

WLMC holds the following Federal Permits and Registrations:

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EPA Hazardous Waste #NVR000092916 (EPA)

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Explosive Permit #9-NV-009-20-8K-00321 (Ledcor CMI Inc. - contract mining)

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POO and Reclamation Plan #NVN86663 (BLM)

The mine also required permits from various State of Nevada agencies including: Bureau of Air Pollution Control (BAPC), Bureau of Mining Regulation and Reclamation (BMRR), Bureau of Sustainable Materials Management (BSMM), Department of Conservation and Natural Resources (DCNR), NDEP and Nevada Department of Wildlife (NDOW).

The State of Nevada requires operational mining permits regardless of land status of the mine (i.e., private, or public). The following are the state permits that are required for the Isabella Pearl mine:

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Reclamation Permit #0387 (NDEP/BMRR)

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Hazardous Waste Generator #NVR000092916 (NDEP/BSMM)

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Water Pollution Control Permit #NEV2009102 (NDEP/BMRR)

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Emergency Release, Response, and Contingency Plan (NDEP/BMRR)

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Spill Prevention, Control, and Countermeasures Plan (NDEP/BMRR)

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National Pollutant Discharge Elimination System (NPDES) General Permit #NVG201000 (NDEP/BWPC)

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General Stormwater Permit #NVR300000 MSW-43292 (NDEP/BWPC)

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Storm Water Pollution Prevention Plan (NDEP/BWPC)

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Water Rights –#89667, 89668 and 89669 (formerly #83484, 82498, 79096, 83485 and 89001T) (DCNR/NDWR); Permits to change the point of diversion and place of use of the water rights have been approved, for groundwater production wells

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Air Quality Class II Operating Permit #AP-1041-3853 (NDEP/BAPC)

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Air Quality Mercury Permit to Construct #AP-1041-3895 (NDEP/BAPC)

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Air Quality Class I Operating Permit to Construct #AP-1041-3897 (NDEP/BAPC)

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Industrial Artificial Pond Permit #41228, Mine ID #MN-013 (NDOW)

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Bureau of Safe Drinking Water Public Water Source Permit NV0001178

WLMC has obtained a Special Use Permit and Building Permits issued by Mineral County to construct buildings at the Isabella Pearl mine including:

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Mineral County Business License #17288 (Mineral County Sheriff’s Office)

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Special Use Permit #165957 (Mineral County Planning Commission)

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Septic Permit #7905 and 7906 (Mineral County Building Department)

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ADR Building Permit #5891 (Mineral County Fire Marshall)

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Office Building Permit #7888 (Mineral County Fire Marshall)

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Water Tank Building Permit #7921 (Mineral County Fire Marshall)

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Isabella Pearl Mine S-K 1300 Technical Report Summary

By virtue of the mine’s location and current land ownership, the mine operations were subject to reclamation financial surety requirements set by the BLM and State of Nevada. The cost associated with final reclamation and closure of the Isabella Pearl mine is currently set at $12.5 million.

1.8	Capital Costs, Operating Costs and Financial Analysis

1.8.1

Capital and Operating Costs

WLMC has provided an estimate of capital and operating costs in this report.

Total Isabella Pearl Mine LOM capital expenditures are estimated to be US$ 1.055 million. The capital costs are based on vendor and specialist quotations. Additional contingencies have been applied to these estimates for omissions. The support for capital and operating costs are based on quotations and estimates in 2022 dollars. No inflation factors have been used in the economic projections.

Mining costs are based on actual costs derived from the Isabella Pearl mine. These costs comprise ore and waste drilling and blasting, loading, and hauling and all the associated site maintenance including, pits, roads, stockpiles, dumps, tailings storage facilities, and storm water controls etc.

Processing costs are based on actual processing costs including but not limited to reagent consumption and current prices for wear and replacement parts.

Current supervisory and administrative support staff numbers are sufficient to efficiently handle the administrative, technical and management functions required for the mining operation. Provisions for training, and regulatory mandated safety functions are also included.

The Isabella Pearl Mine LOM Operating Cash Costs per Tonne Processed is estimated at US$40.85 per tonne. This is based on a total ore processed of 0.9 million tonnes (1.0 million short tons). The estimated remaining mine life is 2 years, with continued gold production from the leach pad for a 3^rd year.

According to the American Association of Cost Engineering (AACE) International, these capital and operating cost estimates based on a production budget and realized costs to date would be classified as Class 1, with an accuracy range of -3% to -10% to +3% to +15%.

1.8.2

Economic Analysis

WLMC has provided an economic analysis in this report.

The Isabella Pearl mine has a 2-year mine-life given the mineral reserves described in this report. The financial results of this report have been prepared on an annual basis. Capital and operating costs are based on realized costs, quotations and estimates in 2022 dollars. No inflation factors have been used in the economic projections. The analysis assumes static conditions for the gold market price over the two-year mine-life. The gold and silver prices were set at $1,750/oz and $21/oz, respectively. These prices are based on the consensus 2023-2024 average prices (CIBC, 2023).

This economic analysis is a post-tax evaluation and is based on a base case $1,750 per ounce gold price and an assumption that the gold would be recovered over the remaining 2-year mine-life.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

The economic results, at a discount rate of 5%, indicate a Net Present Value (NPV) of $85.1 million (after estimated taxes). The following provides the basis of the Isabella Pearl LOM plan and economics:

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A mine life of 2 years, with continued gold production from the leach pad for a third year;

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An average operating cost of $384/ Au ounces-produced;

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Sustaining capital costs of $1.055 million and a mine closure cost estimate of $12.2 million;

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The analysis does not include any allowance for end of mine salvage value.

1.9	Conclusions and Recommendations

1.9.1

Interpretation and Conclusions

Isabella Pearl is a producing gold mine with a favorable economic projection based on current operating costs and detailed LOM mining and processing plan. The Isabella Pearl deposit has the grade and continuity required for on-going production.

The Isabella Pearl deposit geology is generally well understood, and structural geology and alteration are the primary controls on mineralization. The core of the deposit is relatively well-defined but recent infill and step-out drilling has materially changed the current mineral resource model, increasing the confidence level of the mineral resource estimate, and allowing conversion of a significant portion of this material to mineral reserve. Drilling to the northwest of the deposit also has the potential to extend the mineral resources. In addition, reconnaissance geological mapping and rock chip sampling have delineated new, surface high-grade gold target areas further along strike to the northwest of the Isabella Pearl deposit.

Certain factors pose potential risks and opportunities, of greater or lesser degree, to the estimate as the mineral resources are based on currently available data. The highest risks associated with key estimation parameters were identified as:

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Core Recovery: Rock Quality Designation (RQD) results show a wide range of recoveries, which may bias assay grades.

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Bulk Density: Significant voids may reduce recoverable tonnage (Specific gravity is not well constrained).

The predicted mineral resource grades are confirmed at the mining scale using blast-hole drilling results and grade control modeling.

Reconciliations are performed on a monthly basis by the operations department in order to track and compare actual tonnages and grades to the estimated values in the block model. To date, the reconciliations have proved that the estimated tonnages are in line with the values in the block model and that actual grades are slightly higher than estimated, especially in the Pearl deposit.

All refractory sulfide material has been treated as waste for the Isabella Pearl estimate of mineral resources. In addition, the bottom of the optimized pit shell is designed to stay above the water table.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

The conversion of mineral resources to mineral reserves required accumulative knowledge achieved through LG pit optimization, detailed pit design, scheduling and associated modifying parameters. The quantities of material within the designed pits were calculated using a cut-off grade of 0.33 g/t Au which is based on the consensus 2023-2024 average price $1,750/oz Au sales price used for this mineral reserve estimate (CIBC, 2023). The Proven and Probable mineral reserves as of December 31, 2022, reported for the Isabella Pearl mine, using diluted grades, is 0.91 million tonnes (1.00 million short tons) of material at an average gold grade of 2.02 g/t Au (0.059 opst) and 22 g/t Ag (0.6 opst) containing 59,400 ounces of gold and 640,600 ounces of silver. The mineral reserve estimate presented herein is based on technical data and information available as of December 31, 2022.

Isabella Pearl is a disseminated gold and silver deposit with mineralization close to the surface. The mine design consists of one main pit accessing the Isabella Pearl deposit. Open pit mining is by conventional diesel-powered equipment, utilizing a combination of blasthole drills, wheel loaders, and 91-tonne (100-short ton) trucks to handle ore and waste.

The Isabella Pearl oxide ore is amenable to heap leach cyanidation with a high relative recovery and fast leaching kinetics.

The Isabella Pearl mine is economically viable at the consensus 2023-2024 average gold price of $1,750 per ounce gold as well as at the current higher gold prices and has significant economic potential given the possibility for gold price increases in the future (CIBC, 2023). Additionally, there is opportunity to expand the mineral reserve through additional drilling. Cost improvements and further optimizations are also possible.

The Isabella Pearl mine’s economic viability is generally at risk from changes in external factors which would lead to increased input costs, or a fall in the price of gold which would reduce revenue. A decrease in gold price would not only reduce revenue but would also reduce the amount of economically mineable ore as a decrease in metal prices could result in a higher cut-off grade. Under the current gold price environment, the mineral reserves are considered robust.

Environmental and future permitting risks include items being discovered on the mine site such as sensitive or endangered botany, or cultural artifacts. No environmental and permitting risks have been identified.

Internal risks, specific to the Isabella Pearl mine, include:

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Current drill spacing is considered adequate but there is a low risk of a decrease in mineral resources due to additional drilling and subsequent re-modeling and re-estimations.

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Poor operational execution, with resultant cost and schedule over-runs, scope creep, and increased operating costs. This is mitigated by management overseeing production.

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Predicted gold recovery from the Isabella Pearl ore is based on the results of column-leach tests and actual results could be lower than expected. This risk is deemed to be low, given the numerous metallurgical tests that have been conducted on the Isabella Pearl mineral resources during the past 30 years.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

●

Finding and keeping the skilled employees required to operate the Isabella Pearl mine has proven to be challenging, given its rural location. Inadequate staffing can increase operating costs by reducing operating efficiencies and increasing repair and maintenance costs. Recruiting costs might be higher than predicted.

The Qualified Persons (QP’s) preparing this report for WLMC recommend continued open pit mining and processing the ore by screening, stacking, heap leaching and ADR to produce gold doré for sale.

1.9.2

Recommendations

The QP’s preparing this report for WLMC recommend that the Isabella Pearl mine continue with open pit mining and processing the ore by screening, stacking, heap leaching, ADR and doré production. Some additional studies are recommended that may improve value and optimizations including additional drilling to convert mineral resources to mineral reserves.

Recommendations for mineral resource and reserve drilling at the Isabella Pearl mine are shown in Table 1-4. The estimated cost of the recommendation for 9,982 m (32,750 ft) of RC and core drilling totals $2,631,300. The cost of this recommended work has not been included in the Isabella Pearl cash-flow model.

Table 1-4 : Summary Budget for Proposed Exploration Drilling at Isabella Pearl Mine

Description	TOTALS ($USD)
ISABELLA PEARL EXPLORATION
1233 IP-Exploration Subtotal – Core 457 m (1,500 ft)	$323,000
1234 Scarlet Project Subtotal - RC 6,477 m (21,250 ft)	$1,532,000
1235 Wildhorse Project Subtotal – RC 3,048 m (10,000 ft)	$776,300
ISABELLA-PEARL EXPLORATION TOTAL – 9,982 m (32,750 ft)	$2,631,300

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Introduction

2.1	Terms of Reference and Purpose of the Report

Convergent was contracted to update a Technical Report Summary (TRS) on the Isabella Pearl mine, an open pit gold heap leach operation located in Mineral County, Nevada for the Walker Lane Minerals Company (WLMC). WLMC is an indirect, wholly-owned subsidiary of FGC. The TRS is to support of the required annual reporting of FGC.

The quality of information, conclusions, and estimates contained herein is consistent with the level of effort by the QP’s, based on: 1) information available at the time of preparation, 2) data supplied by outside sources, and 3) the assumptions, conditions, and qualifications set forth in this report. The responsibility for this disclosure remains with WLMC.

This report provides mineral resource and mineral reserve estimates, and a classification of mineral reserves prepared in accordance with §§ 229.1300 through 229.1305 (subpart 229.1300 of Regulation S-K) referred to simply as “S-K 1300” in this report.

2.2	Source of Data and Information

WLMC has relied on information and technical documents listed in the References section of this report which are assumed to be accurate and complete in all material aspects.

The reader is referred to earlier reports on mineral resources and reserves and the feasibility study for a more detailed description of the sources of information relied upon by the QP’s of WLMC (Brown et al, 2018, 2021; Hulse et al, 2022).

2.3	Details of Inspection

Ralston Pedersen, Ricardo Garcia and Barry Devlin are the QP’s who visited Isabella Pearl mine on December 12, 2022. In addition, QP’s Ricardo Garcia, Barry Devlin, Fred Brown and Joy Lester have visited the mine on numerous occasions since 2016.

2.4	Previous Reports on Mine

This report updates a previous report titled “S-K 1300 Technical Report Summary, Isabella Pearl Mine, Mineral County, NV” dated February 25, 2022 (Hulse et al, 2022).

The effective date of this report is December 31, 2022.

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Property Description and Location

3.1	Location

The Isabella Pearl mine is located in the Gabbs Valley Range, approximately 10 km (6 mi) north of the town of Luning in Mineral County, Nevada. The closest town with full services is Hawthorne located 40 km (25 mi) to the west (Fig. 3.1). The mine is located within all or portions of the following Townships, Ranges, and Sections relative to the Mount Diablo Baseline and Meridian:

●

Township 8 North, Range 34 East, Section 03; and

●

Township 9 North, Range 34 East, Sections 26, 27, 34 and 35.

The approximate center of the deposit areas is Latitude N38.60° and Longitude, W118.18° (UTM 397,665 E, 4,273,011 N, Zone 11). The mine has good connections to the infrastructure of west-central Nevada, with access roads to the mine site linking to Nevada state route 361 and US Route 95, the main highway between Reno and Las Vegas.

Figure 3-1 : General Location Map of the Isabella Pearl Mine

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3.2	Area of the Property

The Isabella Pearl mine area covers approximately 627 hectares (1,549) acres) and consists of 90 unpatented lode mineral claims on land owned by the U.S. government and administered by the BLM. WLMC controls 100% interest in the Isabella Pearl claims which are subject to a 2.75% NSR royalty. WLMC also controls an additional 478 claims covering approximately 3,329 hectares (8,227 acres) along a approximate 26 km (16 mi) trend extending northwest of the Isabella Pearl mine.)

3.3	Mineral Titles, Claims, Rights, Leases and Options

Mineral claims in the mine area are shown in Figure 32. The claims within the mine area controlled by WLMC, its entities, or partners are listed in Table 31 and are current as of December 31, 2022.

Currently, annual claim maintenance fees are the only federal payments related to unpatented mining claims. Annual maintenance fees of $100,572 were paid to the BLM during 2022 to hold the 568 unpatented lode mining claims. In addition, fees for filing a Notice of Intent (NOI) totaling $6,852 were paid to Mineral County in order to hold the claims for another year.

There are no Tribal, State of Nevada or U.S. Forest Service lands within the mine area.

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Figure 3-2 : Isabella Pearl Mine Area Mineral Claims Map

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Table 3-1 : List of Unpatented Lode Mineral Claims for the Isabella Pearl Mine


Claim Count	Claim Name & Number	Claim Type	Location Years	Owner	Acquisition History
16	VULTURE DOG 1 – 16	Unpatented Lode	1979	WLMC	Acq From TXAU
7	ISABELLA #12 – 15, ISABELLA #16 FRAC - 17 FRAC and #19 FRAC	Unpatented Lode	1980	WLMC	Acq From TXAU
3	ISABELLA #1 – #3	Unpatented Lode	1982	WLMC	Acq From TXAU
1	VULTURE DOG 22	Unpatented Lode	1984	WLMC	Acq From TXAU
18	SODA #6 - 13, #19, #23 – 26, #36 and #49 - 52	Unpatented Lode	1987	WLMC	Acq From TXAU
2	SODA #37 - 38	Unpatented Lode	1990	WLMC	Acq From TXAU
2	SODA #5 and 32	Unpatented Lode	1991	WLMC	Acq From TXAU
2	TDG-1 - 2	Unpatented Lode	2008	WLMC	Acq From Gateway Gold (USA) Corp.
21	IS 1 – 4, 6, 8, 10, 12, 14, 16, 18, 31 – 32, 34, 36, 38, 40, 50 - 53	Unpatented Lode	2016	WLMC	Acq From Nevada Select Royalty
9	SODAR 20 – 22, 33 – 35 and 46 - 48	Unpatented Lode	2018	WLMC	Acq From TXAU (WLMC relocation of SODA claims)
1	TDGR-3	Unpatented Lode	2020	WLMC	Acq From Gateway Gold (USA) Corp (WLMC relocation of TDG-3 claim)
8	SCR S1 – S8	Unpatented Lode	2021	WLMC	Staked by WLMC
90	Claim Total

3.4	Other Significant Factors and Risks

The mine is in production, and the QP's are not aware of any factors or pending changes that would impact the continued operation or its profitability.

3.5	Royalties and Agreements

WLMC owns an undivided fifty percent (50%) interest and leases the remaining fifty percent (50%) interest in ten (10) claims from Natasha Matkin-Hayes et al of Las Vegas, Nevada. This affects the following claims:

●	Isabella Claims 1, 2, 3, 12, 13, 14 and 15, and

●	Isabella Fractions 16, 17, 19.

The Matkin-Hayes lease, dated April 1, 1992, was recorded by memorandum dated June 15, 1992, in Book 146 OR, page 978 (Mineral County, Nevada), and executed by Sarah D. Narkus, Natasha Matkin-Hayes, William Longhurst, John Longhurst, Caroline Merrick, Marguerite Cole, and Combined Metals Reduction Company (CRMC). TXAU succeeded to CMRC’s interest in the lease pursuant to a Trustee’s Deed, dated August 13, 1999, recorded May 14, 2004, Doc # 131124, executed by First American Title Insurance Company in Favor of TXAU. WLMC purchased a 50% undivided interest in lessor’s interest in the lease including a 50% interest in a 6% gross receipts production royalty, and a 50% ownership of the subject property. WLMC received an assignment of the lessee’s interest in the lease. The assignment of the lessee’s interest in the lease transferred the benefit of advance royalty payments that had been paid to lessors through August 2016, in the amount of $459,800.

On October 23, 2018, Ely Gold Royalties Inc., through its wholly owned subsidiary Nevada Select Royalty, Inc., entered into a binding letter agreement with a private individual to acquire 100% of all rights and

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interests in 0.75% (three quarters of one percent) of the 3% NSR royalty on the 10 Isabella claims controlled by the Matkin-Hayes Lease.

WLMC owns 100% interest in the remaining 26 of the 36 claims comprising the Isabella Pearl mine subject to a reservation of a 3% net smelter return (NSR) royalty and royalty agreement in favor of TXAU. This affects the following claims:

●	Vulture Dog 1, 2, 3, 4, 5, 6, 7, 8, 10 and 22,

●	Soda 8, 32, 36, 37, 38, 49, 50, 51 and 52, and

●	Sodar 21, 33, 34, 35, 46, 47 and 48.

On March 6, 2019, WLMC acquired 100% of all rights and interests in the TDG-1, 2 and 3 claims held by Gateway Gold (USA) Corporation (Gateway) subject to a reservation of a 3% NSR royalty and royalty agreement in favor of Gateway. These 3 claims are within the Isabella Pearl mine area.

On October 29, 2020, Nevada Select Royalty Inc. assigned to Gold Resource Corporation (GRC), currently FGC, the parent company of WLMC, fifty percent (50%) of its one-fourth (25%) royalty interest of the 3% gross receipts royalty payable from production at the 10 Isabella claims controlled by the Matkin-Hayes Lease.

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Accessibility, Climate, Local Resources, Infrastructure and Physiography

4.1	Topography, Elevation and Vegetation

The mine is within the Basin and Range province, a major physiographic region of the western United States. The region is typified by north-northeast trending mountain ranges separated by broad, flat alluvium filled valleys. Locally, the mountain ranges trend northwesterly, making this area rather anomalous in relation to typical Nevada physiography. Elevations on the mine site range from a minimum of 1,597 m (5,240 ft) in the valley to a maximum of 1,777 m (5,829 ft) at the uppermost elevation.

Typical high desert vegetation, controlled in part by elevation, is present in the area, including Pinion Pine and Juniper trees, wild rosebush and several varieties of sagebrush, cacti, and short grasses.

4.2	Accessibility and Transportation to the Property

The mine site is in Mineral County and is accessible from Hawthorne, Nevada via well maintained paved roads and maintained dirt roads. From Hawthorne, travel east on U.S. Highway 95 40 km (25 mi) to Nevada State Route 361 which is just west of the town of Luning. Turn north on State Route 361 and travel approximately 8.4 km (5.2 mi) to the county-maintained Rabbit Springs Road that turns off to the west. The mine site lies about 1.6 km (1 mi) to the north along a dirt road that turns off approximately 1.6 km (1 mi) west of State Route 361. Mine roads provide access within the mine site and are passable by high clearance two-wheel drive vehicles. The mine area, encompassing about 436 hectares (1,078 acres) (see Figure 4.1), is located at the west foot of the Gabbs Valley Range in all or parts of Sections 27, 34 and 35 of Township 9 North, Range 34 East and Section 3 of Township 8 North, Range 34 East, Mount Diablo Baseline & Meridian (MDB&M).

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Figure 4-1 : Isabella Pearl Mine Access

4.3	Climate and Length of Operating Season

The climate is dry, semi-arid, with annual precipitation of approximately 11.4 cm (4.5 in), as documented at the nearby Mina Meteorological Station. Average temperatures range from -3° to 10° C (26° to 50° F) in the winter to highs exceeding 32° C (90° F) in the summer. Historically, the record low temperature, recorded in January 2003, is -19° C (-3° F), and the record high temperature, recorded in July 2002, is 42° C (108° F). The general area is drained by numerous stream channels originating in the mountains. These are typically dry but carry some runoff onto alluvial fans and into playas during summer thunderstorms.

The mine is accessible and can be operated year-round.

4.4	Sufficiency of Surface Rights

All mineral resources and mineral reserves in this report are located on unpatented lode mining claims controlled by WLMC. WLMC has sufficient claims to cover all surface operations for the life of mine. As described elsewhere in this report, WLMC has secured and maintained the necessary permits for exploration and development of the Isabella Pearl mine.

4.5	Infrastructure Availability and Sources

4.5.1

Power

Power is currently supplied by three diesel-powered electric generators. One 1500 kW generator is on-line, one 1500 kW generator is on standby and another 200 kW generator is on standby for the production wells to generate power for the well pumps if the need arises. The total connected force in the plant, including the crushers, is approximately 1,567 hp. WLMC has installed 4,160 volt direct burial power lines

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from the generator yard throughout the site and to the production wells, IPPW-1, IPPW-3, and IPPW-4. Fuel for the generators is stored in two above-ground tanks on graded areas with HDPE-lined floors and berms for secondary containment to provide emergency capture of 110-percent of the largest fuel tank/vessel volume.

4.5.2

Water

Industrial water is supplied from three production water wells. Production Well #2 (IPPW-2) was completed in September 2013 to a depth of 128 m (420 ft) and is upgradient from both the heap leach and open pit. IPPW-2 was proven to have limited water supply capabilities and is currently not in use. Production Well #1 (IPPW-1) was installed in October 2016 to a depth of 396 m (1,300 ft) and is located south of the processing facility. Production Well #3 (IPPW-3) was installed in August 2019 to approximately the same depth as Well #1 and is also located south of the processing facility. Production Well #4 (IPPW-4) was installed in April 2022 to a depth of 390 m (1,280 ft) and is located south of the processing facility. Permits for the production water wells and a maximum of 242 acre-feet of water annually (0.5 cubic feet per second (ft³/sec) have been issued by the Nevada State Engineer.

4.5.3

Mining Personnel

There is considerable expertise in mining operations and management available from population centers within about 240 km (150 mi) of the mine. Nevada is an active mining state, with emphasis on open-pit gold operations. Mining personnel have been drawn from the cities of Reno/Sparks, Carson, Fernley and Fallon, the towns of Hawthorne and Yerington, as well as from other smaller communities in west-central Nevada. WLMC manpower currently totals 56 full-time employees.

4.5.4

Tailings Storage Area

The current heap leach operation does not include any tailings. Spent ore from the heap leach pad remains on the synthetic liner upon which it was constructed. Heap closure is addressed in the plan of operations (POO).

4.5.5

Waste Disposal Area

The primary waste-rock disposal area is a valley fill located to the south of the Isabella Pearl main pit.

4.5.6

Heap Leach Pad Area

The heap leach pad site a has sufficient capacity for the planned operation and potential expansion. It is also proximal to a water source and the mining areas to optimize operational efficiency.

4.5.7

Processing Plant Site

The location of the processing plant is adjacent to and down-gradient of the heap leach pad facilitating gravity flow of solutions.

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History

The Isabella Pearl mine is in the Santa Fe Mining District which lies within the Walker Lane Mineral Belt. Although the district was discovered in the late 19th century, no work on the Isabella Pearl mine area was done until the 1930’s when the Gilbert brothers completed a 120 m (400 ft) drift at Isabella. The brothers encountered up to one ounce of gold per ton in spots, but no economic material was produced. The Gilbert brothers then worked the Civit Cat mine, located about 1.6 km (1 mi) to the west (different than the Civit Cat North portion of the Isabella Pearl mineral resources and reserves discussed herein), and were rumored to have produced $80,000 worth of gold.

5.1	Prior Ownership and Ownership Changes

The Isabella mine was held by B. Narkaus until 1978 and was subsequently leased by Joe Morris the same year. Mr. Morris and three partners re-located some of the Isabella claims and subsequently leased them to the Combined Metals Reduction Company (Combined Metals). In 1987, Combined Metals entered into a joint-venture with Homestake Mining Company (Homestake) to explore and develop the Isabella claims and surrounding areas. The Combined Metals-Homestake joint venture was terminated in 1990. Combined Metals continued to maintain the claims but encumbered the property by borrowing over two million dollars from Repadre International Corporation (Repadre). Repadre initiated foreclosure action in 2002, and Combined Metals immediately filed for bankruptcy to forestall the foreclosure. In March 2004, the note held by Repadre was purchased by TXAU Investments Ltd. and TXAU Development Ltd., both Texas corporations (TXAU). The Combined Metals bankruptcy action was dismissed in May 2004, the note was foreclosed on, and the Isabella Pearl mine mining claims (including the 36 claims covering the Isabella, Pearl and Civit Cat deposits) were transferred to TXAU.

On August 12, 2016, Walker Lane Mineral Corp.’s (WLMC) parent company GRC (predecessor company prior to spin-off to FGC) acquired all of the outstanding stock of WLMC, a private entity held by TXAU, which controlled the Isabella Pearl mine, in exchange for 2,000,000 shares of GRC’s common stock valued at $13.1 million and cash of $152,885. At the time of acquisition by WLMC, the Isabella Pearl mine was in the advanced stages of engineering and production permitting.

5.2	Exploration and Development Results of Previous Owners

In the early 1970's, Ventures West Minerals Ltd. and Brican Resources formed a joint venture for exploration of the general area around the Isabella Pearl mine. Later in the decade, the joint venture with Westley Explorations, Inc., successor to Ventures West, discovered low-grade gold mineralization in the Santa Fe Mine area, just south of and across the highway from the Isabella Pearl mine. In 1983, the Santa Fe property was joint ventured with Lacana Gold Inc., and later 100% interest was acquired by Lacana’s successor, Corona Gold Inc. The Calvada deposit, just to the east was explored by a CoCa Mines Inc. - Amax Gold Inc. joint venture prior to purchase by Corona Gold. The Santa Fe and Calvada mines, along with two other satellite deposits, were subsequently developed by Corona Gold as the Santa Fe open pit mine and heap leach operation. In 1992, Corona Gold was acquired by Homestake which completed mining at Santa Fe in December 1994. In late 2008, the Santa Fe property was acquired and further explored by Victoria Gold Corp. (Victoria). In 2021, Victoria sold the Santa Fe property to Lahontan Gold Corp.

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In 1980, Fischer-Watt Mining Company acquired claims, northwestward from the Santa Fe mine property, for the purpose of exploring for bonanza gold-silver vein systems. They completed a stream sediment geochemical survey and a rock geochemical survey in portions of the property, fluid inclusion temperature determinations, some alteration mapping, and additional claim staking. Fischer-Watt subsequently joint-ventured the property with Ventures West Minerals, and additional work included geologic mapping at a scale of 1 inch = 500 feet, additional rock chip geochemistry, limited induced polarization and resistivity geophysical surveys, and nine rotary and DDH holes in the Copper Cliffs West exploration area. Although the drill holes did not encounter economic mineralization, Fischer-Watt concluded: “…the HY system clearly warrants further evaluation”. Combined Metals subsequently entered into a joint venture agreement with Fischer-Watt in 1982. That joint venture was dissolved during 1983 with Combined Metals acquiring Fischer-Watt’s interest in the claims. These claims, along with the acquisition of additional claims and leases, including the Isabella claim group assembled by Norsemont Mining Corporation in 1984, ultimately totaled more than 1,000 claims along the northwesterly trend.

Combined Metals drilled the Isabella deposit plus a limited number of exploration holes in a few of the other exploration areas during its joint venture with Homestake from 1988 through 1990. The joint venture drilled at least 175 RC and DDH holes before the joint venture was terminated.

TXAU conducted a DDH drilling program in early 2007 that consisted of 19 holes for a total of 1,187 m (3,894 ft) of HQ-sized core. This drilling was designed primarily to provide material for metallurgical testing and confirm the historic assay and geological data collected by the Combined Metals- Homestake joint venture at Isabella and Pearl. In 2008, TXAU completed an additional 7 DDH holes for a total of 1,129 m (3,704 ft) in the Pearl deposit in order to address some issues concerning assays and insufficient quality assurance/quality control measures from prior drilling.

5.3	Historical Production

In the late 1970’s, Joe Morris placed a small amount of crushed material onto a small pad with the intention of developing a heap-leach operation, but the venture was abandoned (Diner, 1983). No record of gold production from this heap leach operation is available.

5.4	Isabella Pearl Mine Production

Since production commenced at the Isabella Pearl mine in 2019, a total of 2,810,662 tonnes of open pit ore has been mined to produce 128,052ounces of gold and 139,540 ounces of silver (Table 51). In May of 2019, WLMC began selling gold and silver doré from the Isabella Pearl mine.

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Table 5-1 : Isabella Pearl Mine Production 2019 - 2022

Year	Ore Mined Tonnes	Gold Produced Oz	Silver Produced Oz
2019	934,723	10,883	9,752
2020	643,518	29,479	28,359
2021	598,345	46,459	44,553
2022	634,076	41,231	56,876
Totals	2,810,662	128,052	139,540

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Geological Setting, Mineralization and Deposit

The following description of geology and mineralization was mainly based on work by Ekrin and Byers (1985) with modifications and minor editing excerpts from Golden (2000), Hamm (2010) and Prenn & Gustin, 2008, 2011 & 2013).

6.1	Regional Geology

The Isabella Pearl mine is located in the central portion of the Walker Lane, a major northwest- trending zone on the western border of Nevada characterized by a series of closely spaced dextral strike-slip faults that were active throughout much of the middle to late Cenozoic. It is a complex zone up to 300 km (186 mi) wide and 1,000 km (620 mi) long that lies on the western boundary of the Basin and Range Province.

Volcanic rocks of middle Tertiary age cover much of the property and include intermediate lava flows and ignimbrite ash flow sheets. The volcanic rocks unconformably overlie Mesozoic strata including Triassic and Jurassic sedimentary units and Cretaceous and Jurassic igneous units. Tectonic activity and erosion have left an irregular, dominantly buried surface of Mesozoic rocks. Within the regional Walker Lane tectonic setting, several major fault zones trend through the property and are dominated by various splays and offset branches. The Soda Springs Valley fault zone is a major host of mineralization in the area and particularly along the Pearl fault strand. The combined right-lateral, post-mineral displacement along the regional faults is in excess of 10 km (6 mi).

A regional geologic map is presented in Figure 6-1 showing the location of the Isabella Pearl mine. A regional cross section also demonstrates the rotation of blocks like the Isabella Pearl setting.

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Figure 6-1 : Isabella Pearl Mine Regional Geologic Map

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6.2	Local and Property Geology

The Isabella Pearl deposit is situated in the central portion of the Walker Lane geologic belt, which is a major structural zone, 90-300 km (60 to 190 mi) wide, that separates the Sierra Nevada and the Great Basin structural provinces, and which extends from the Las Vegas region northwestward, beyond Reno, for a total length of 800 km (500 mi). The Walker Lane zone is documented to be at least as old as 28 Ma (million years), with initial extension in a north to north-northeast direction and characterized by west-northwest to northwest-trending strike-slip faults that are primary controls for mineralization. These Tertiary-age faults are thought to be reactivated older structures present in the basement rocks.

The known pre-Tertiary basement rocks in the area include the Triassic Luning Formation, which is composed of medium to thick-bedded limestones with some dolomite and siliciclastic rocks. This formation was intruded by stocks and dikes of Jurassic or Cretaceous diorite, porphyritic quartz monzonite, and granite. These basement rocks are overlain by a thick sequence of late Oligocene ash flow tuffs that exceeds 1 km (3,300 ft) in thickness and includes minor associated lavas and intrusive rocks. From oldest to youngest, these Oligocene units include: (1) the Lavas of Giroux Valley; (2) the Mickey Pass Tuff, the Singatse Tuff, and the Petrified Spring Tuff, which are members of the Benton Spring Group; and (3) the Blue Sphinx Tuff. These units are overlain by the early to middle Miocene Lavas of Mount Ferguson, and they are locally crosscut by associated rhyolitic intrusions. The volcanic rocks range in age from 16 to 29 Ma. Other precious-metal districts of the central Walker Lane are temporally and spatially related to volcanic rocks of similar ages. See Figure 62 for a stratigraphic column of the Isabella Pearl mine area.

Figure 63 shows a representative section through the Isabella Pearl deposits, corresponding to Section A-A’ on Figure 64. Note that the ore bodies are controlled by faults that have opposing dips. Also highlighted in light blue is the tabular-style Isabella deposit. Figure 64 shows a map of the local and property geology.

The most active volcanism occurred 28-24 Ma and included tuff units that appear to be altered by the approximately 19 Ma mineralizing event(s). From youngest to oldest these locally hydrothermally altered units, which consequently are potential host rocks, are listed as follows:

●

Tbx brecciated tuff and lava unit Miocene or Oligocene Blue Sphinx Tuff Petrified Spring Tuff

●

Singatse Tuff

●

Mickey Pass Tuff

●

Lavas of Giroux Valley

The Lavas of Giroux Valley do not outcrop within the property boundaries.

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Figure 6-2 : Isabella Pearl Mine Stratigraphic Column

Figure 6-3 Cross Section through the Isabella Pearl Mine; view NW.

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Figure 6-4 : Isabella Pearl Mine Geologic Map

6.2.1

Lithology

Lithology plays a role in mineral control. Age dating suggests that any unit older than the Lavas of Mount Ferguson are potential host rocks. Altered and/or mineralized volcanic outcrop areas that have been recognized to date, listed from the youngest to the oldest rocks, are as follows:

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●

The Singatse Tuff is present locally throughout the trend, and although it is not known to contain economic gold mineralization, it is commonly hydrothermally altered, particularly in the basal portion, and locally it may have acted as a cap for underlying mineralization. Alteration in this and the younger units described above may represent leakage of mineralization from the more receptive Guild Mine Member beneath.

●

The Isabella deposit is hosted within moderately to poorly welded tuff in the upper rhyolitic portion, and the Pearl deposit is hosted dominantly within densely welded tuff in the lower, rhyodacite portion of the Guild Mine Member of the Mickey Pass Tuff.

●

The basal air fall tuff unit of the Guild Mine Member is a potentially favorable host rock. Fragments of carbon and organic trash contained within the unit could react with mineralizing fluids and precipitate precious metals in a manner very similar to the carbon circuit of a cyanide recovery plant.

●

The Pearl and Civit Cat sulfide mineral resources are hosted in part by the Cretaceous "granite".

6.2.2

Structural Geology

The Walker Lane zone is documented to be at least as old as 28 Ma (million years). The Walker Lane structures can be summarily described as consisting of numerous northwesterly trending strike-slip and normal faults, along with extensional oblique fractures and other faults that formed between the northwest striking faults, and dominantly pre-mineral detachment and associated listric normal faults. These structures provided both the ground preparation and the hydrothermal conduit systems necessary for economic mineralization.

Several regional and deep penetrating fault zones trend northwest through the area of interest including the Soda Springs fault. An example of the general density and trend of faulting is illustrated in Figure 6.3, which covers the area in the vicinity of the Isabella deposit. Many more faults are present than shown, but at all practical surface map scales individual faults and related fractures and joints are so numerous, and commonly obscured by alteration, that only the principal ones have been mapped. The importance of faults and fault zones for ore localization, particularly at intersections of and at bends along them cannot be over-emphasized.

Geologists who have worked in mineralized areas along the trend have observed the following: both pre-mineral and post-mineral faults are present, which respectively have structurally prepared the host rocks and displaced mineralization; post mineral faults are commonly characterized by unconsolidated breccias rather than by slickensides; tectonic, hydrothermal, and crackle breccias are present locally; and multiple episodes of breaking and healing are documented. At least some mineralization is reported to occur along the flanks of grabens and half-grabens formed by second and third order structures.

6.2.3

Alteration

In the mine area, argillized rocks have been described as dominantly an illite-montmorillonite assemblage, with kaolinite generally restricted to narrow bands up to a few yards wide around silicified zones. Weakly argillized rocks are variably bleached and locally contain areas of less altered, propylitized rock. Strongly to intensely argillized rocks are white and very incompetent, weather down readily, and the original rock type is unrecognizable in the field; pyrite is generally abundant, and where oxidized the rocks are yellowish

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to greenish in color. Argillized rocks contain no silicification other than single quartz veinlets. Light pink alunite is present locally as replacements in feldspar sites. In some areas, this strong argillic alteration may be underlain by propylitic alteration. There may be a relationship between alteration features and the intrusions of rhyolite dikes and plugs.

At the Isabella deposit, weak to strong argillic alteration is pervasive in the upper, poorly to moderately welded ash flow tuff, while the lower, more densely welded tuff generally appears relatively "fresh" although varying degrees of propylitic alteration are common. In the upper, less welded tuff, narrow, structurally-controlled zones of silica-pyrite, as well as the more pervasive, near-horizontal, blanket-like silica replacement bodies, cut across the tilted host rock and generally grade outward into silica-kaolinite, with local alunite envelopes, and then into pervasive illite-montmorillonite zones.

Calcite, an alteration product of plagioclase, is present locally as pods and veinlets. Near silicified fault zones epidote is present as small granules both in plagioclase phenocrysts and in the groundmass.

Noteworthy is the fact that silicification and argillization features overlying the Isabella deposit are essentially identical to the alteration features present elsewhere along the structural trend.

Alunite is also commonly present in silicified areas, and silicified rocks generally grade outward into argillized and then into propylitically-altered rocks. Silicification is localized by fault and shear zones, and in many areas, silica has replaced large masses of both the volcanic and granitic rocks. Gold and silver are associated with this silicification within the Guild Mine Member of the Mickey Pass Tuff.

Geologic records indicate that, in many or most areas, the quartz-alunite mineral assemblage caps argillic alteration. It has been hypothesized that this assemblage may have resulted from a strong acid leaching stage originating in a vapor-dominated hydrothermal system. These silicified outcrops locally stand in bold relief as knobs and irregular ledges, and silicification can cover hundreds of square yards.

Silicified cap rocks are reddish to purplish in less altered areas and white (no sulfides) in the most intensely altered areas. Other geologic data distinguish two types of silicification that have been described: (1) strong to intense silicification is pervasive, with the rock matrix partially to completely replaced by silica and with the rock texture partially to completely destroyed; iron oxides are common, and alunite and occasional barite may be present, and (2) weak to moderate silicification described as “irregular”, with "case hardened", goethite-stained rocks that form ledges in which the feldspars are bleached. Other types of silicification may indicate concealed faults.

6.3	Isabella Pearl Mineralized Zone

The gold-silver mineralized zones discussed in this report include the Isabella, Pearl, and Civit Cat oxide deposits and the Pearl and Civit Cat sulfide deposits, collectively referred to in this report as the Isabella Pearl deposit. Alteration and mineral assemblages at Isabella Pearl, including widespread argillic alteration and generally abundant alunite, indicate the deposits belong to the high-sulfidation class of epithermal mineral deposits. K-Ar age determinations indicate the mineralization is about 19 Ma, some 7 to 10 million years younger than the age of the host rocks. This early Miocene age conforms to the age of other high-sulfidation epithermal precious-metal deposits in the Walker Lane (e.g., Goldfield and Paradise Peak).

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Silicification generally grades outward into argillization, which then grades into propylitically altered rocks. Silicification is localized by faults and shears, and in many areas, silica has replaced large masses of both the volcanic and granitic rocks. Gold is associated with this silicification, occurring primarily within the Guild Mine Member in the lower part of the Mickey Pass Tuff. This alteration assemblage is also present in the lower, more densely welded tuff characteristic of the Pearl deposit, but it is tightly confined around the mineralized core the deposit.

The Isabella mineralization is moderately argillized to highly siliceous, contains numerous vugs in former feldspar and pumice sites (vuggy-silica textures), and typically lacks any evidence of cross-cutting veinlets. Narrow, structurally controlled zones of silica-pyrite, as well as the more pervasive silica replacement bodies, generally grade outward into silica-kaolinite with local alunite envelopes, which in turn grade into pervasive illite-montmorillonite zones. The iron oxide minerals goethite, jarosite, and hematite are present in the siliceous groundmass. Gold occurs as very small (<10 microns) liberated particles in cavities and along fracture surfaces. Rare secondary minerals include barite, cinnabar, and scorodite. A near-horizontal zone of pervasive argillic and advanced-argillic alteration occurs above the Isabella deposit in the upper, poorly to moderately welded rhyolitic ash-flow tuff of the Guild Mine Member. Within this altered zone, alunite occurs as pseudomorphs after potassium feldspar phenocrysts and as replacements of pumice fragments.

The Pearl deposit is hosted by the lower, densely welded portion of the Guild Mine Member and, to a lesser extent, by Cretaceous granite. Mineralization is largely controlled by the northwest-striking, northeast-dipping contact zone between the granitic basement and the overlying Tertiary volcanic units. This contact may be partially or entirely faulted; this report assumes the contact is marked by the fault. Strong silicification accompanies gold mineralization and is associated with fracture fillings and replacement of the welded tuff. The mineralization is usually associated with strong brecciation. Multiple stages of fracturing and brecciation with associated silicification have been observed in drill core.

Sulfide minerals at Pearl commonly exceed ten percent (by volume) and are composed primarily of crystalline grains and aggregates of pyrite, colloform banded “melnikovite”-type pyrite, and bladed marcasite (or pyrite after marcasite) in dark microcrystalline quartz. This quartz has replaced both the volcanic and intrusive host rocks. In the granite, alteration has resulted in the complete leaching of feldspars and ferromagnesian silicates, and pyrite and marcasite have filled the voids left by the silicate dissolution. Rare sulfide minerals observed in thin and polished sections include arsenopyrite, pyrrhotite, galena, sphalerite, chalcocite, chalcopyrite, polybasite, and pyrargyrite. Other minerals include very minor magnetite, zircon, monazite, and rutile. Native gold has not been observed in the sulfide mineralization.

The oxidation boundary is depressed over and immediately around the Pearl deposit, with oxide mineralization extending to more than 150 m (500 ft) below the surface. Goethite, jarosite, and manganese oxide are common, and barite and chlorargyrite occur rarely in the siliceous groundmass. Gold within the oxide mineralization occurs both as locked and liberated particles, as well as electrum. Particles range in size from 2 to 34 microns, averaging 14 microns. The liberated particles occur as small wire-like grains in cavities, while the locked gold is encapsulated by silica or goethite.

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The Civit Cat mineralization, which is relatively minor and poorly defined by drilling, lies to the northeast of Pearl, and is associated with the northwest-striking, southwest-dipping Civit Cat fault. The control on mineralization by the Pearl and Civit Cat faults, which have similar strikes but opposing dips, results in northwest-trending, roughly lens-shaped zones of mineralization that flank both sides of a graben-like structural trough.

6.3.1

Fluid Inclusion Data

Fluid inclusion studies document approximately 12 coarse-grained “vein” quartz bearing outcrops located north and east of the Isabella Pearl mine area (Diner, 1983). Investigation of polished sections yielded 234 inclusions (which were divided into two types: liquid and vapor dominated). The inclusions were measured for homogenization temperatures and indicated a range from 200 to 310 °C with most temperatures in the 220-230 °C range. These temperatures are consistent with boiling conditions.

Salinities were determined and reported in the range of 1-3.05 Wt% NaCl throughout the system with the average at 1.80 Wt% NaCl; this range is consistent with boiling conditions in mineralizing epithermal systems.

The liquid-dominated inclusions contained 2-50% vapor with the majority very low at 5%; however, the range is consistent with boiling if trapped at the same time. A rare occurrence of an abnormally high temperature (> 400 °C) was noted for one sample suggesting trapping of mixed phase fluids, again indicative of boiling. The vapor-dominated inclusions contained >90% vapor and one sample vaporized upon heating. This sample was collected from near the historic Santa Fe open pit mine and corresponded with an excessively high homogenization temperature; in addition, this sample reported the highest salinity at just over 3%.

Diner (1983) noted that fluid inclusion data were on par with deposits of similar style (e.g., Bodie, California 215-245 °C, Tonopah 250-300 °C and Comstock 250 °C) and the temperature range was consistent for this type of solution to exist in equilibrium with gold-quartz-pyrite and could carry enough gold in solution, as auriferous chloride complexes, to account for the hydrothermal gold ore deposit, at the given salinities.

In association with fluid inclusions, Diner (1983) considered pressure effects on the mineralizing system. It was concluded that mineralization could extend to depths of 850 to 320 m; with corresponding hydrostatic pressures of 106-67 bar (max) to 85-32 bar (min), and with corresponding lithostatic pressures of 365-167 bar (max) to 212-80 bar (min). The pressure range likely fluctuated due to sealing and breaching of the conduits thus lowering the pressure below hydrostatic. Diner went further, stating that normal boiling condition pressure at the top of the Mickey Pass Tuff was likely 30-60 bar; and concluded that the presence of the quartz-alunite ‘blanket” at the given pressure and temperature ranges was indicative of an acid leaching vapor phase environment.

6.4	Deposit Type

Alteration and mineral assemblages throughout the deposit are represented by widespread argillic alteration, generally abundant alunite, and the presence of minor amounts of base metals, all of which indicate the ore deposits to belong to the high sulfidation (acid sulfate) class of epithermal mineral

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deposits. Fluid inclusion data indicates the solutions that deposited the coarse-grained quartz were dilute, with a salinity of 1-2 weight percent NaCl and temperatures ranging 200 to 300° C. Temporal relationships and the thickness of the tuff units suggest that the depth of formation was more than 900m. In Figure 65 a red circle highlights the high sulfidation characteristics of the Isabella Pearl ore classification including the Na-rich, moderate temperature, and acid phase minerals. The geometry of the deposit is controlled by two dominant geologic features; favorable stratigraphic horizon, and structural connectivity to mineralizing fluids. In high sulfidation environments the fluids ascend via structural feeders and under acid attack particularly replaces more favorable units; in the case of Isabella Pearl the Guild Mine member of the Mickey pass Tuff was this unit.

A local stratigraphic section shown in Figure 66 illustrates a specific model for mineralization at the Isabella deposit and elsewhere along the Walker Lane trend, where numerous fault zones provided the conduits necessary for hydrothermal fluids to transport gold into environments favorable for gold mineralization. The uppermost, Isabella-type deposit occurs in the upper portion of the Guild Mine Member tuff host rock. This deposit type is relatively large and of lower average grade because the tuff is less welded and consequently relatively porous, allowing the mineralizing fluids to spread beneath the overlying Singatse Tuff, which served as a relatively impermeable barrier (only the lower portion of the Singatse Tuff is altered in the vicinity of the Isabella Pearl deposit).

The stratigraphically lower Pearl-type deposit is limited to faults and fractures and is controlled in part by the basement rock contact with the overlying volcanic rocks. The deep sulfide and Pearl-type deposits are relatively high-grade because these environments were the first favorable environments encountered by ascending, mineralized, hydrothermal fluids.

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Figure 6-5 : High Sulfidation Characteristics of the Isabella Pearl Mineralization

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Figure 6-6 : Idealized Stratigraphic Section Highlighting Mineralization Controls for Isabella Pearl

6.4.1

Extents and Continuity

Within the Isabella Pearl mine area, six primary gold deposits have been modeled: Isabella, Pearl, Civit Cat North, Scarlet South (excluding Scarlet North), Silica Knob and Crimson. The approximate pre-mining extents of each are summarized in Table 61. Each deposit shows internal geological and grade continuity, with a consistent direction of mineralization. The approximate dimensions of each deposit are based on grade shells constructed at a nominal 0.3 g/t Au (0.009 opst) used to limit grade interpolation in the 3D block model.

Table 6-1 : Approximate Extents of Gold-Silver Deposits in the Isabella Pearl Mine Area

Deposit	Tonnage	Strike Length	Dip Length
Civit Cat North	3.4 million tonnes	290 m	250 m
Isabella	7.1 million tonnes	570 m	20 m
Pearl	4.0 million tonnes	400 m	280 m
Scarlet South	0.5 million tonnes	550 m	100 m
Silica Knob	0.3 million tonnes	300 m	100 m
Crimson	1.2 million tonnes	560 m	70 m

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Exploration

7.1	Exploration by Previous Operator (TXAU)

TXAU conducted two DDH drilling programs that were managed by HB Engineering. The first program was designed primarily to provide material for metallurgical testing, as well as to attempt to confirm the historic assay and geological data collected by the Combined Metals-Homestake joint venture. A total of 19 holes totaling 1,187 m (3,894 ft) were drilled in early 2007, including four holes into the Pearl deposit and the remaining holes into the Isabella deposit. Two holes, P-6 and P-16 were lost in bad ground and were re-drilled. P-16 recovered core to 10 m (33 ft), which was split and sampled; no core from P-6 was sampled.

The 2007 drill data were incorporated into the project database, and MDA was contracted to complete a mineral resource estimate, as well as an economic scoping study (Prenn and Gustin, 2008). These studies led to the identification of a number of deficiencies that precluded the classification of any of the resources as Measured. In order to address these deficiencies and lower project risk, TXAU completed the 2008 drill program, which consisted of 7 DDH holes for a total of 1,129 m (3,704 ft) of drilling. Since the Pearl deposit contributes approximately 75% of the total oxide resources at Isabella Pearl, and essentially all of the sulfide resources, the 2008 drilling concentrated on the Pearl deposit.

The 2008 program included an industry standard QA/QC program, down-hole surveys were conducted on all holes, care was taken during drilling and the removal of core from the core barrel in order to maximize sample recoveries, and further specific gravity determinations were obtained from samples of the drill core. Additional QA/QC work was also completed on the 2007 drill samples, and geologic mapping of portions of the Isabella-Pearl resource area was completed.

In addition to the drilling programs, TXAU commissioned McClelland Laboratories, Inc. (McClelland) to complete metallurgical testing on a bulk surface sample and DDH composites in 2007 and 2008. The results of this test work are summarized in Section 13.

7.2	Exploration by WLMC

7.2.1

Surface Exploration

The Isabella Pearl deposit geology is generally understood, with favorable stratigraphy, structural geology, and alteration as the primary controls on mineralization. The core of the deposit is also relatively well-defined but mining and additional drilling can be expected to increase the current mineral reserves and the confidence level of the mineral resource estimate. Potential exists to extend the mineral reserves by drilling along the periphery of the deposit to the south, northwest, and northeast.

WLMC has also conducted extensive rock-chip sampling and geological mapping adjacent to the current Isabella and Pearl deposits to the northwest of the deposits as well as minor sampling south of the Pearl deposit. A total of 196 rock chip samples were taken by WLMC in 2017 in the Scarlet anomaly immediately northwest of Isabella and Pearl deposits and analyzed by Inspectorate - Bureau Veritas Minerals Laboratory (Bureau Veritas) in Sparks, Nevada. Rock chip samples were analyzed for gold, silver, and a

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multi-element suite. A total of 67 of the 196 rock chip samples returned greater than 0.30 ppm Au and 22 of the 196 samples returned greater than 1.0 ppm Au with a high of 9.278 ppm Au.

Reconnaissance geological mapping and rock chip sampling has also identified new, surface high-grade gold target areas located along strike to the northwest of the Isabella Pearl mine into the Scarlet area (Figure 71), as well as the already defined Civit Cat North deposit to the northeast. Figure 71 also highlights exploration targeting near the Isabella Pearl mine at the Scarlet and Civit Cat North area. Here we can see the usefulness of spectral sample analysis as a tool for targeting in conjunction with rock chip sampling, which aided in delimiting local fault strands hosting potential gold mineralization. 3D modeling and interpretation of the data has identified additional targets. Historical drilling was widely spaced with favorable results that were not offset with additional drilling, and WLMC plans to offset these historical drill intercepts as well as test highly anomalous rock chip samples and targets generated in modeling.

Figure 7-1 : Local rock chip sampling and spectral data modeling

In 2022 along with the expansion of the IP mine development area, WLMC expanded its exploration efforts northwest of the IP mine into the Twin Hills and Prospect Mountain target areas (black box) (Fig. 7.2 and Fig. 7.2). Exploration included follow up of historic CMR rock chip and soil geochemical grid studies along the favorable Walker Lane structural trend where the same Isabella-style mineralization is hosted

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in the prospective Mickey Pass volcanic host rocks. One particularly large gold-arsenic-mercury anomaly was defined (with soils reporting > 0.05 ppm gold, with anomalous values reporting 0.1-0.89 ppm gold) corresponding to a twin topographically high area of remnant silica cap. Historic rock chips reported from 0.30 to 0.737 ppm gold. The area was defined by CMR as the Twin Hills anomaly (Fig. 7.2).

Figure 7.2 Regional Alunite Mineral Map from Aster data for the IP Mine (red outline) and Twin Hills Prospect Mountain Target Area (yellow box).

An adjacent area of interest, Prospect Mountain presents anomalous gold in similar host volcanic rocks along a large southwest facing hillside northeast of Twin Hills. The area hosts occurrences of pervasive alunite alteration in intensely faulted, silicified, and argillized volcanic rocks. A 0.1 ppm northwest trending gold anomaly was defined in soils, and 13 historic rock chips from the area reported 0.678 to 1.33 ppm gold.

CMR had undertaken scout drilling as part of a Phase I program utilizing rotary drilling and four shallow holes were tested in the Twin Hills targeting shallow oxide ore; TS-24 (drilled to 300 foot) and TS-30 (drilled to 150 feet) tested within the soil gold geochemical anomaly and no significant gold values were

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encountered. Six holes were completed at Prospect Mountain area; results were poor. It was noted the targeting did not adequately test the structural controls nor the Pearl-style mineralization.

WLMC exploration efforts included follow-up mapping, rock chip, and Aster analysis (Advanced Spaceborne Thermal Emission and Reflection Radiometer data- spectral reflectance definition of minerals). Figure 7.2 highlights historic geochemically anomalous areas and Aster mineral mapping of alunite highs in the Twin Hills and Prospect Mountain areas.

During 2022 WLMC collected nearly 150 rock chip samples with results reporting up to 5.00 ppm gold for the Twin Hills area. A geostatistical analysis was performed and contouring of the values (inverse distance weighted) showed a strong correlation to the Twin Hills mineralized area and the previous CMR historic soils geochemical anomaly (Fig. 7.3). Currently the company has drill targets defined for a 2023 RC drilling program to test the potential deeper oxide ore, structural controls (feeders), and Pearl-style mineralization at the Twin Hills area.

Figure 7.3 Gold in ppm Inverse Distance Grid of 2022 WLMC Surface Rock Chips for the Twin Hills Area.

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7.2.2

Geophysics

Geophysical targeting with regional magnetics offers another exploration tool for the Isabella Pearl mineralized trend. Figure 7.2 highlights contoured total magnetic response data. Target blocks identified in conjunction with the tectonic reconstruction are colorized in red. Block B shown in Figure 7.2 is interpreted as the offset, northwestern portion of the Isabella Pearl target (Block A).

The Isabella Pearl land position hosts many exceptional target areas. Based on indications by previous exploration and a good understanding of characteristics defining the Isabella Pearl deposit, further exploration can be targeted at prospects hosted along the same structural corridor and locally the fault strands, within same prospective rock units (i.e., Mickey Pass Tuff). In particular, future exploration targeting should focus on:

●

Silicification and quartz flooded zones along high angle faults,

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Silicification and quartz flooded zones with in favorable permeable units of the volcanic stratigraphy; especially where they are in contact with high angle faults,

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Silicification and quartz flooding associated with other less permeable volcanic sediments lying between the basement rocks and fed by high angle faults,

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Targeting alunite-dickite and other higher temperature clay alteration minerals,

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Exploration techniques including spectral analysis in conjunction with detailed field mapping, in combination with regional spectral data, and

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Geophysical data review and further geophysical studies regional targeting.

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Figure 7-2 : Schematic image of regional magnetic contour data (after Lockwood. et al, 1971)

7.2.3

Remote Sensing

The use of spectral data in vectoring to higher temperature alteration can be very useful given the documented alteration footprint. In addition, to local targeting with grid sampling and spectral analysis, regional targeting for gold exploration can search for the products of hydrothermal alteration where mineral-bearing rocks were displaced by strong geothermal systems.

In April 2020, Terra Modelling Services Inc. (TMS) completed data acquisition, processing and analysis of an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data set for the Isabella Pearl mine, including the Scarlet area, shown in Figure 7.3. Analysis of the ASTER data included:

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Granule ID from the raw data;

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Band identifiers, both ASTER band and USGS reference;

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Band ratios used and spatial resolution charts;

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Structural interpretation;

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Quartz content map;

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Differentiations of argillic, phyllic, propylitic, and silicic alterations;

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Characterization of areas for illite, crystalline kaolinite, dickite and possible vegetation anomalies;

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●

All ferric and non-ferric oxides (jarosite, goethite, hematite).

Anomalous high hydrothermal alteration spectral analysis identified 9 target areas for ground follow-up in the Isabella Pearl mine and Scarlet areas (Figure 74). Potential mineral targets are mostly aligned with major NW-trending structures and have spectral and vegetation anomalies.

Previous to the 2020 analysis of ASTER data by TMS, a computer enhanced Landsat image was analyzed by Analytical Imaging and Geophysics (Hamm, 1999). Figure 7.5 highlights enhanced regional spectral data on the Landsat image. The image represents a computer enhanced 2° X 2° Landsat image from an altitude of 708 km with a resolution of 78 km2 per pixel (Gabbs Valley Range, Nevada Landsat TM ratios 5/7, 3/1, ¾ RGB). Six discrete spectral wavelengths of reflected light from visible to mid-infrared, and one band in the thermal infrared was recorded simultaneously. Shades of red indicate vegetation, lakes are purple, valley soils are light blue and evaporative alkali flats appear white. White and light-yellow colors correspond to higher temperature alteration and presence of clays or silica (after Hamm, 1999). Historic mines of the Santa Fe district shown as blue stars. Anomalies corresponding to clays, silica and sulfate minerals produced by hydrothermal alteration are depicted as white to light yellow, and often can be found associated with precious metal occurrences.

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Figure 7-3 : Quartz Content (Upper), and Alunite Content (Lower) for Isabella Pearl, including Scarlet Area

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Figure 7-4 : Scarlet area Potential Target areas based on ASTER data analysis identified by TMS.

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Source: ENVI by Analytical Imaging and Geophysics, Boulder, Colorado 1997; WRS path 42, Row 33, 7, July 1984 UTM zone 11)

Figure 7-5 : Isabella Pearl Mine (yellow star) and WLMC land package on a Landsat image.

7.2.4

Drilling

The mineral resources and mineral reserves reported herein were estimated using a drill hole database compiled by WLMC, as described below. The final mine database includes a total of 616 holes drilled by Combined Metals-Homestake, TXAU and WLMC at Isabella Pearl through 2022, including 576 RC, 37 DDH and three metallurgical DDH drill holes. Metallurgical drill holes were submitted in their entirety for metallurgical testing and do not have individual assay results. The Isabella Pearl mine drilling history is summarized in Table 71, which includes drill holes shown in Figure 7.6.

Most of the pre-TXAU and WLMC drilling was completed between 1987 and 1990 by the Combined Metals-Homestake joint venture (Golden, 2000). It should be noted that the database used by Sierra Mining reportedly included 178 Combined Metals-Homestake holes (Golden, 2000), three more than the MDA database; holes IC-34, 35, 37, and 175 are possibilities for missing holes in the MDA data based on the drill hole numbering sequence (Prenn & Gustin, 2008, 2011 & 2013).

Topographic surveying of collars was undertaken by registered professional surveyors from Nevada. All plots were delivered as stamped referenced plats along with corresponding digital data files. Verification of field locations were also validated with registered air photographs. The TXAU 2007 - 2013 drill hole collar locations were surveyed by David Rowe of Winnemucca, Nevada. Rowe also surveyed the collar

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locations of 100 Combined Metals-Homestake holes that could be accurately located on the ground. The WLMC 2016 - 2018 drill holes were surveyed by Kevin Haskew of Reno, Nevada. The 2019-2022 drill hole collars were surveyed by the Isabella Pearl mine survey department.

Table 71 : Drilling History at the Isabella Pearl Mine (1987 - 2022)

Company	Period	RC		DDH (Core)		Total
Company	Period			No.	Meters	No.	Meters	No.	Meters
Combined Metals-Homestake	1987-1990	182	19,598.6	6	513	188	20,111.6
TXAU	2007-2008	-	-	26	2,315.7	26	2,315.7
WLMC*	2016-2022	394	35,640	5	442.8	399	36,082.8
WLMC Met Holes	2016-2017	-	-	3	659.9	3	659.9
Totals		576	55,238.6	40	3,931.4	616	59,170
*Includes 6 Air Track (AT) drill holes

Figure 7-6 : Isabella Pearl Mine Drill Hole Location Map

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7.2.4.1

RC Drilling Procedures

Logs are available for all historic holes in the sequence IC-38 through IC-178, except IC-54. All historic holes are believed to have been completed by RC drill rigs, with the exception of DDH holes IC-136 through IC-141.

Drilling Services is identified as the drill contractor for 33 of the holes in the sequence from IC-142 through IC-174. A total of 43 logs from holes in this sequence note the drill type as being TH100 or TH100A. Holes IC-142 to IC-156 are noted as being drilled in 1989, while holes IC-158 through IC- 174 were drilled in 1990.

Hackworth is noted as the drill contractor for holes IC-176 through IC-178, the latest Combined Metals-Homestake holes in the database (IC-175 is not in the database). These holes were drilled in 1990 using a TH60 rig.

Drill-bit diameters are identified on 128 of the RC logs, which indicated 5.125, 5.25, 5.5 and 6-inch bit sizes. Most of the Hackworth holes were drilled with 5.5-inch bits, while most Drilling Services holes were drilled with 5.25 inch bits. Both drill contractors used hammer and tri-cone bits

WLMC 2016 - 2022 RC drilling was mainly performed on diurnal shifts by New Frontier Drilling LLC (Frontier) Fallon, Nevada. Drilling equipment used by Frontier consisted of an RC track mounted Foremost MPD drill capable of drilling angle holes to 500 m (1,500 ft). In September 2022, Major Drilling America Inc. (Major) was contracted for an additional 20,000 feet of RC drilling at Isabella Pearl. This program was primarily targeted at deep sulfide mineralization on the Pearl and Civit Cat North structures. Major ran 3 crews for 24 hours on a 12-hour shift per crew during a 20-day rotation, using a Schramm 455 track mounted RC drill rig with a 1050CFM/350PSI compressor. This drill is capable of drilling to 1800 ft depth.

The samples were recovered through the center of the double walled pipe and the sample discharged via a cyclone. Water/fluid was injected into the airflow on an intermitted to continuous basis to assist with recovery of the sample through the wet rotating splitter. Appropriate sample bags were provided by WLMC and they were collected and bagged and tagged under geologist supervision during the drilling. The contractor conducted all operations to industry standard practices.

In 2017, WLMC also utilized New Frontier Drilling to complete a 1,356 m (4,450 ft) RC condemnation drill program to ensure no mineral resources occurred where mine/plant facilities are currently located. The program consisted of 5 RC drill holes drilled to depths of up to 366 m (1,200 ft).

The air track (AT) drilling was completed by Merritt Construction Mina, NV utilizing an Atlas Copco portable blast hole rig modified to 4.5 inches for shallow drilling (less than 30m (99 ft)). The drill rig is supported by compressed air at a rate of 825 cubic feet per minute, with compressed air forced down the center of the rod and hammered materials returned up the outside of the rod. This drilling method was restricted to vertical hole orientation. The drilling method was dry, samples were taken for each 1.5m (5 ft), and the recovered chips were collected in 5-gallon pails and split with a portable riffle splitter. Samples were bagged at the site and transported to company’s secure storage location until submittal to ALS. The AT holes were not surveyed down-hole.

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7.2.4.2

DDH (Core) Drilling Procedures

Combined Metals-Homestake completed a six-hole DDH drilling program in 1989. No further details concerning this program are available.

TXAU conducted a 19-hole DDH drilling program in 2007 and drilled an additional seven DDH holes in 2008. HB Engineering managed the drilling programs for TXAU. Leroy Kay Drilling Co., Inc. of Yerington, Nevada (Kay Drilling) was the drilling contractor for the 2007 program. All recovered core was HQ size (2.5 in).

The drilling contractor for the 2008 program was Sierra Madre Exploration of West Point, California (Sierra Madre). Sierra Madre used a track-mounted Longyear Casa Grande C5S rig, made in Italy specifically for drilling long DDH holes from underground. The rig is capable of drilling HQ core to depths of greater than 600m (2,000ft) and can drill angle holes on very small drill pads, which was important for the 2008 campaign. To help increase recovery in loose, difficult drilling conditions, a Longyear’s HQ3 system was used instead of a standard core barrel. Water pressure was used to pump the core out of the core barrel (as opposed to jarring it out with hammer blows) onto a half-pipe tray, and the core was then boxed in standard wax-coated cardboard boxes.

KB Drilling Company (KB) of Mound House, Nevada provided services for the 2016 metallurgical DDH drilling program. Two sizes of DDH drill core were utilized: a large diameter “PQ” 8.5 cm (3.35 in) for metallurgical testing, and a smaller “HQ” 63.5 mm (2.5 in) for core sample and routine laboratory analyses. Core was pressure removed when possible (in fractured ground) otherwise handled traditionally with rubber mallet percussion to remove. Core was place in wax treated boxes. Depth, rod change, and loss zones were noted on wood blocks in place with the drill core. Core was shipped to a WLMC locked storage in Hawthorne, Nevada twice daily at drilling shift change. After drilling holes were surveyed with the Reflex tool (described in next section) and logged paper copies of the measurements were retained by the drill site geologist. The contractor conducted all operations to industry standard practices.

7.2.4.3

Down Hole Surveying Procedures

For the historical drilling the database contains down-hole survey data for the 11 DDH holes (including metallurgical drill holes), 5 RC holes and 6 AT holes as listed in Table 71. The remaining drill holes are limited to collar surveys only.

Seven DDH holes drilled by TXAU in 2008 were surveyed by the drillers upon completion of each hole using a Reflex EZ-SHOT tool. The holes tended to steepen by 1 to 2.5 degrees and change azimuth unsystematically up to 5.5 degrees. If the pre-2008 drill holes, which do not have down-hole survey data, deviated at similar magnitudes as the 2008 holes, the lack of surveys would have no material impact on the mineralization model.

The WLMC 2016 DDH program under KB utilized a Reflex EZ-shot camera and surveys were taken at approximately 50 ft intervals as per industry standard. The data was reviewed by the competent geologist and approved for entry into the company database.

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The 2017 condemnation RC drilling program utilized the Reflex EZ-Gyro and surveys were taken every 15.2 m (50 ft) as per industry standard and included a QA/QC multi-shot optimization at approximately each 30.5 m (100 ft). This data was reviewed by competent geologist and approved for entry into the company database. No extreme or unusual deviation was noted with the survey results from either campaign.

In 2016, WLMC also completed six (6) shallow AT drill holes totaling 82m (269 ft) targeting shallow oxide mineralization in the Isabella Pearl mine area. Holes were completed to maximum depth 30 m (99 ft.). In addition, the WLMC 2017 condemnation RC drilling program sterilized all near-surface ground in the areas tested with drill holes consisting of mainly alluvium or uneconomic mineralization to final drill hole depths.

During 2022, WLMC completed 45 in-fill and step-out RC drill holes to expand mineral resources at the Isabella Pearl mine. The drilling program utilized the New Frontier Drilling and Major RC drill rigs and the same industry accepted down hole Reflex surveying and laboratory analytical methods as previously. The drilling campaigns successfully intercepted additional mineralization both along known structures and increased confidence in other infill areas. Results included up to 7.21 g/t Au over 21.34 m and 6.25 g/t Au over 41.15 m including 12.17 g/t Au over 6.10 m in Hole IPRC-353, 2.86 g/t Au over 44.20 m including 5.07 g/t Au over 16.76 m in Hole IPRC-357 and 3.78 g/t Au over 35.05 m including 6.45 g/t Au over 13.72 m in Hole IPRC-358. These intercepts were returned from the known Pearl, Civit Cat, Crimson and Scarlet structures. The significant intercepts have also been designated as either oxide or non-oxide. Oxide intercepts are defined by assays having a cyanide leach/fire assay ratio greater than 0.4. Oxide intercepts are reported at a 0.3 g/t Au cutoff, whereas non-oxide intercepts are at a 0.6 g/t Au cutoff.

Figure 7.7 shows drill holes completed during 2022 and Table 72 summarizes significant assay results. All of the information gained has been included in mineral resource and reserve estimates reported herein.

7.2.5

Material Results and Interpretation

The TXAU 2008 and WLMC 2016 - 2022 drill information allowed for the refinement in the modeling of the high-grade portions of the Pearl deposit, as well as the oxidized/unoxidized boundary and the contact between Tertiary volcanic and granitic rocks. These refinements are critical to the confidence in the resource estimation at Pearl. Down-hole surveys conducted on the 2008 holes indicated only minor deviations, which alleviated concerns related to the lack of down-hole survey data in the pre-2008 holes. The confirmatory drilling ultimately led to the definition of mineral resources and reserves within the Pearl deposit reported herein.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Figure 7-7 : Location Map for Drill Holes Completed at Isabella Pearl Mine during 2022

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Table 7-2 : Significant Results 2022 Drilling at Isabella Pearl Mine^*

Hole #

Angle

Target

From

Interval

deg

g/t

IPRC-347

-75

Crimson

45.72

53.34

7.62

0.41

oxide

IPRC-348

-55

Crimson

53.34

56.39

3.05

1.00

oxide

67.06

71.63

4.57

0.40

IPRC-349

-75

Crimson

77.72

88.39

10.67

0.58

oxide

IPRC-350

-55

Crimson

62.48

82.30

19.81

0.49

oxide

IPRC-351

-75

Crimson

54.86

76.20

21.34

0.39

oxide

97.54

100.58

3.05

0.74

IPRC-352

-75

Crimson

59.44

67.06

7.62

0.34

oxide

79.25

82.30

3.05

0.70

88.39

96.01

7.62

0.56

incl.

89.92

91.44

1.52

1.25

IPRC-353

-90

Pearl

0.00

21.34

7.21

oxide

incl.

0.00

3.05

15.15

incl.

12.19

13.72

1.52

11.10

incl.

19.81

21.34

1.52

11.20

21.34

62.48

41.15

6.25

non-oxide

incl.

24.38

28.96

4.57

10.67

incl.

47.24

53.34

6.10

12.17

67.06

68.58

1.52

1.00

IPRC-354

-45

Pearl

36.58

39.62

3.05

2.21

non-oxide

50.29

64.01

13.72

4.67

incl.

50.29

53.34

3.05

11.91

IPRC-355

-55

Pearl

44.20

60.96

16.76

6.47

non-oxide

incl.

50.29

54.86

4.57

13.34

IPRC-356

-46

Pearl

30.48

45.72

15.24

3.21

non-oxide

incl.

30.48

36.58

6.10

4.58

54.86

60.96

6.10

10.40

incl.

56.39

57.91

1.52

16.90

incl.

59.44

60.96

1.52

15.60

IPRC-357

-54

Pearl

18.29

62.48

44.20

2.86

non-oxide

incl.

44.20

60.96

16.76

5.07

IPRC-358

-54

Pearl

7.62

42.67

35.05

3.78

non-oxide

incl.

9.14

10.67

1.52

5.56

incl.

22.86

36.58

13.72

6.45

IPRC-359

-88

Pearl

0.00

18.29

3.72

oxide

35.05

38.10

3.05

2.29

non-oxide

IPRC-361

-70

Pearl

118.87

129.54

10.67

1.96

non-oxide

incl.

120.40

123.44

3.05

4.17

138.68

149.35

10.67

1.08

IPRC-362

-50

Pearl

150.88

153.92

3.05

1.15

non-oxide

161.54

175.26

13.72

1.74

incl.

169.16

172.21

3.05

3.66

IPRC-363

-72

Pearl

70.10

74.68

4.57

0.97

non-oxide

79.25

99.06

19.81

1.74

incl.

89.92

92.96

3.05

4.17

105.16

134.11

28.96

1.10

incl.

109.73

111.25

1.52

1.72

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175.26

181.36

6.10

1.14

incl.

179.83

181.36

1.52

1.73

IPRC-364

-70

Civit Cat

25.91

35.05

9.14

0.37

oxide

140.21

144.78

4.57

0.65

non-oxide

IPRC-365

-51

Civit Cat

24.38

36.58

12.19

1.29

oxide

incl.

25.91

28.96

3.05

2.65

124.97

128.02

3.05

0.78

non-oxide

IPRC-366

-71

Pearl

79.25

118.87

39.62

1.25

non-oxide

incl.

80.77

88.39

7.62

2.43

143.26

152.40

9.14

0.64

incl.

149.35

152.40

3.05

1.01

176.78

182.88

6.10

0.82

incl.

176.78

178.31

1.52

1.60

IPRC-367

-52

Pearl

85.34

88.39

3.05

0.81

non-oxide

99.06

111.25

12.19

1.81

incl.

106.68

111.25

4.57

2.60

121.92

123.44

1.52

0.98

167.64

173.74

6.10

1.11

IPRC-368

-70

Pearl

80.77

89.92

9.14

2.07

non-oxide

incl.

88.39

89.92

1.52

7.00

96.01

102.11

6.10

1.34

109.73

123.44

13.72

1.19

incl.

109.73

111.25

1.52

2.36

149.35

152.40

3.05

0.84

IPRC-369

-51

Pearl

76.20

85.34

9.14

1.24

non-oxide

115.82

147.83

32.00

1.36

incl.

123.44

128.02

4.57

3.46

incl.

143.26

146.30

3.05

2.18

IPRC-371

-71

Civit Cat

22.86

32.00

9.14

1.34

oxide

incl.

24.38

27.43

3.05

2.17

129.54

150.88

21.34

1.19

non-oxide

incl.

146.30

147.83

1.52

2.21

IPRC-372

-51

Civit Cat

15.24

25.91

10.67

0.70

oxide

124.97

135.64

10.67

1.58

non-oxide

incl.

126.49

128.02

1.52

2.18

incl.

132.59

134.11

1.52

2.21

IPRC-373

-84

Civit Cat

30.48

32.00

1.52

0.91

oxide

146.30

167.64

21.34

0.90

non-oxide

incl.

155.45

160.02

4.57

1.49

175.26

178.31

3.05

1.05

IPRC-375

-51

Civit Cat

143.26

153.92

10.67

1.17

non-oxide

incl.

143.26

144.78

1.52

2.45

161.54

164.59

3.05

0.68

IPRC-376

-71

Civit Cat

144.78

147.83

3.05

0.72

non-oxide

IPRC-377

-49

Civit Cat

152.40

160.02

7.62

1.05

non-oxide

IPRC-378

-71

Civit Cat

184.40

187.45

3.05

1.35

non-oxide

IPRC-379

-50

Civit Cat

172.21

181.36

9.14

0.98

non-oxide

incl.

173.74

176.78

3.05

1.62

IPRC-380

-63

Pearl

15.24

25.91

10.67

0.38

oxide

230.12

237.74

7.62

0.70

non-oxide

incl.

231.65

233.17

1.52

1.10

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Isabella Pearl Mine S-K 1300 Technical Report Summary

IPRC-381

-78

Pearl

18.29

19.81

1.52

1.14

oxide

205.74

213.36

7.62

1.46

non-oxide

222.50

227.08

4.57

0.78

IPRC-382

-62

Pearl

16.76

19.81

3.05

1.02

oxide

IPRC-384

-81

Civit Cat

13.72

24.38

10.67

0.43

oxide

138.68

153.92

15.24

0.76

non-oxide

incl.

141.73

144.78

3.05

1.30

IPRC-385

-62

Civit Cat

25.91

28.96

3.05

0.45

oxide

120.40

144.78

24.38

0.79

non-oxide

incl.

121.92

128.02

6.10

1.24

incl.

132.59

135.64

3.05

1.09

IPRC-386

-90

Scarlet

210.31

268.22

57.91

0.65

non-oxide

incl.

213.36

214.88

1.52

1.06

incl.

256.03

257.56

1.52

1.25

IPRC-387

-45

Scarlet

44.20

47.24

3.05

1.06

oxide

149.35

156.97

7.62

2.64

non-oxide

incl.

150.88

153.92

3.05

4.09

236.22

239.27

3.05

0.69

243.84

245.36

1.52

0.68

301.75

324.61

22.86

0.84

incl.

304.80

306.32

1.52

1.11

incl.

310.90

312.42

1.52

1.13

^*NOTE: Oxide intercepts defined by assays having cyanide leach/fire assay ratio greater than 0.4. Oxide intercepts reported at 0.3 g/t Au cutoff; non-oxide intercepts reported at 0.6 g/t Au cutoff.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Sample Preparation, Analysis and Security

8.1	Historic Security Measures and Sample Preparation

Historic security measures and sample preparation were reported by MDA (Prenn & Gustin, 2013). This includes descriptions excerpted from Sierra Mining (Golden, 2000) for drilling programs conducted at Isabella Pearl before TXAU took control of the project. For more details, the reader is referred to earlier reports on mineral resources and reserves and the feasibility study for the Isabella Pearl mine (Brown et al, 2018, 2021; Hulse et al, 2022).

8.2	WLMC (2016 to Present)

8.2.1

Security Measures

Sample security procedures for WLMC sample materials were established according to industry standards and included (from generation of sample at the site) secured sample transport to a local locked storage facility for holding and/or directly shipped via secured transport to the laboratory for analysis. Samples were shipped by cargo truck in lots loaded into bins with top closures, enclosed trailer, or stacked and covered and secured to the bed of transport truck (in the case of whole DDH drill hole boxes). Chain of custody forms accompanied the shipments to the reception at the assigned laboratory. No breaches of the security were reported.

8.2.2

Sample Preparation and Analysis

For the WLMC 2016 drilling program, continuous sampling was done on 1.52 m (5 ft) intervals, contingent on drilling conditions. All assay samples were processed at ALS Laboratories in Reno, NV, with additional work carried out at ALS in Vancouver, BC, Canada. WLMC has no business relationship with ALS beyond being a customer for analytical services. ALS is an accredited ISO/IEC 17025 facility.

For the WLMC 2017 - 2022 drilling programs, continuous sampling was again done on 1.52 m (5 ft) intervals, contingent on drilling conditions. All assay samples during the 2017 – 2022 drilling programs were processed either at ALS or Bureau Veritas. Bureau Veritas is an accredited ISO/IEC 17025 facility. WLMC has no business relationship with either ALS or Bureau Veritas beyond being a customer for analytical services.

The umpire laboratory used for check assaying of ALS analyses is Bureau Veritas and vice versa.

All assay samples were analyzed using a 30 g FA with an AAS finish for gold (ALS code AU-AA23; Bureau Veritas code FA430). This technique has a lower detection limit of 0.005 ppm and an upper detection limit of 10.00 ppm. Samples with greater than 10.00 ppm Au were re-analyzed using a 30 g FA with a gravimetric finish (ALS code Au-GRA21; Bureau Veritas code FA530).

All assay samples were also analyzed using a 0.5 g sample with aqua regia for silver (ALS code Ag-AA45; Bureau Veritas code AQ-400). This technique has a lower detection limit of 0.1 ppm for silver and an upper detection limit of 200 ppm for silver.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

8.2.3

Quality Assurance/Quality Control Procedures

All Standard Reference Materials (SRM) used for the QA/QC program were obtained from Shea Clark Smith, Reno, NV and MEG LLC., Lamoille, NV. The variation from the SRM mean value defines the QA/QC variance and is used to determine acceptability of the standard sample assay. Approximately 60 g of sample material was submitted per QA/QC sample. Blank material was sourced as “Lava Rock” (pumice) from Oxborrow Landscaping, Sparks, NV.

The 2022 WLMC drilling program consisted of 43 RC drill holes. All SRM samples from Shea Clark Smith / MEG, LLC. are listed in Table 81.

Table 8-1 : WLMC 2022 Standard Reference Materials

Standard	Au ppm	Au SD
MEG-Au.17.08	0.41	0.02
MEG-Au.17.21	1.10	0.062
MEG-Au.19.05	0.663	0.057
MEG-Au.19.07	0.311	0.018
MEG-Au.19.09	0.711	0.032
MEG-Au.19.11	1.30	0.029
MEG-Au.21.01	0.407	0.023
MEG-Au.21.05	1.723	0.092

For the SRM, a failure was defined as an assay result outside 2 times the SRM standard deviation. For the 279 SRM samples submitted a total of 109 failures were noted, a failure rate of 38% (Table 82). More than three fourths of all failures were reported for MEG-Au.21.01 (64 failures) and MEG-Au21.05 (31 failures). The QP’s believe that the quality statistics for MEG Au.21.01 and MEG Au.21.05 are inadequate, and it is recommended that the use of this SRM sample be discontinued. Thirteen of the remaining SRM failures are summarized in Table 8-2. Overall SRM performance is shown in Figure 81.

Table 8-2 : 2022 SRM Failures

Sample IDD	SRM	DHID	Lab	Au (g/t)	Failure
292720	MEG-Au.17.08	IPRC-350	ALS	0.459	High
2978651	MEG-Au.17.08	IPRC-359	BV	0.211	Low
292760	MEG-Au.19.05	IPRC-351	BV	0.782	High
4576040	MEG-Au.19.07	IPRC-353	BV	0.362	High
4576260	MEG-Au.19.07	IPRC-358	BV	0.35	High
4578680	MEG-Au.19.09	IPRC-361	BV	0.782	High
4579000	MEG-Au.19.09	IPRC-363	BV	0.783	High
4579260	MEG-Au.19.09	IPRC-364	BV	0.783	High
4579440	MEG-Au.19.09	IPRC-365	BV	0.78	High
4594900	MEG-Au.19.09	IPRC-387	BV	0.776	High
4595040	MEG-Au.19.09	IPRC-387	BV	0.787	High
4594280	MEG-Au.19.09	IPRC-383	BV	0.634	Low
4579020	MEG-Au.21.01	IPRC-363	BV	2.031	High

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Figure 8-1 : 2022 SRM Performance

For the blank material a failure was defined as an assay that exceeded five times the detection limit of 0.005 ppm (Fig. 8.2). Of the 279 blanks submitted, a total of four failures were received (Table 83). A check on the corresponding adjacent SRM sample results for these intervals indicated no issues associated with the individual assays.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Figure 8-2 : 2022 Blank Material Performance

Table 8-3 : 2022 Blank Material Failures

SAMPLE ID	DHID	LAB	Au(g/t)
4576001	IPRC-353	BV	0.311
4576021	IPRC-353	BV	0.098
4576181	IPRC-356	BV	0.029
4579581	IPRC-366	BV	0.048

8.3	Check Assays

8.3.1

Field Duplicates

For the 2022 drilling campaign, a total of 277 field duplicates were taken and submitted for assay at the same laboratory as the primary sample. There is a strong correlation between the primary and secondary assays (Fig. 8.3)

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Figure 8-3 : Au Field Duplicate Control Plot for 2022

For the 2022 drilling campaign, a total of 840 coarse rejects from samples that assayed above 0.20 ppm were submitted for cyanide leach assay. Cyanide leach assay results from samples within the oxide zone demonstrated an average recovery of 92% percent compared to the corresponding fire assay results. Cyanide leach assay results from samples within the sulfide zone demonstrated an average recovery of 10% percent compared to the corresponding fire assay results (Fig. 85).

Figure 8-5 : Cyanide Leach vs Fire Assay Comparison Plot

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Isabella Pearl Mine S-K 1300 Technical Report Summary

8.4	Opinion of Adequacy

Convergent’s QP considers the sample preparation, and analysis carried out are by conventional methods that are common for the industry. Security procedures are consistent with standard practice, and reasonable. The QA/QC protocol produces satisfactory results, with no concerns apparent with the assay results. The QP considers that the 2022 drilling programs and the historical drilling information as reported by MDA (Prenn & Gustin, 2013), meet industry standards and have been reviewed and confirmed in sufficient detail to permit inclusion of the information in the Isabella Pearl mineral resource and reserve database.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Data Verification

It is the Convergent QP’s opinion that there is nothing to date to suggest that there are serious or systemic concerns with the data of the Isabella Pearl site. The data is managed in a secure environment, using off-the-shelf software packages that are up-to-date and appropriate for the tasks to which they are applied. The staff involved are well-trained, competent, and experienced. The QP has used information and technical documents supplied by WLMC and prepared by MDA for the Data Verification sections with regards to the historical drilling programs at Isabella Pearl. For more details, the reader is referred to earlier reports on mineral resources and reserves and the feasibility study for the Isabella Pearl mine (Brown et al, 2018, 2021; Hulse et al, 2022) During the site visit, Convergent reviewed sufficient files and drill cores and cuttings to confirm the previous work.

9.1	Opinion on Data Adequacy

Investigations of all aspects of current and historical data quality indicates that the quality of the information is suitable for mineral reserve estimation.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Mineral Processing and Metallurgical Testing

10.1	Metallurgical Overview

This section provides a description of Isabella Pearl mineralization and metallurgical characterization of the deposit. There have been nine individual test work programs by various operators. The correct identification of metallurgical properties of this material (the geo-metallurgical model) is key to project success.

The results of the cyanide leach test work demonstrate the straightforward and consistent nature of the Isabella Pearl metallurgy.

●

The economic minerals of interest are gold and to a minor degree silver.

●

The results are not dependent on deposit lithology or zoning; The deposit is being mined only above the water table and so refractory sulfide material below the water table is not an issue.

●

A single simple cyanidation process can be used to recover gold and to a lesser degree silver.

●

Fast leaching kinetics.

●

Economics improve by two-stage crushing of plus 1-gram gold to ½ inch. Test work is on-going at the Isabella Pearl laboratory to develop particle size gold recovery relationship.

10.2	Mineralogy and Metallurgical Ore Types

The mineral resources of the mine include the Crimson, Scarlet North and South, Silica Knob, Civit Cat North, Isabella, and Pearl oxide deposits, collectively referred to as the Isabella Pearl deposits. The origin of all these deposits is similar, widespread argillic alteration and generally abundant alunite indicate the deposits are high-sulfidation epithermal mineral deposits. K-Ar age determinations demonstrate that the mineralization is about 19 Ma. Oxide mineralization at Isabella Pearl extends over 150 m (492 ft) below the surface and it should be noted that only oxidized ore is included in economics of the mine plan.

The gold-silver mineralization is closely associated with silicification, which generally grades outward into argillization, which then into propylitically altered rocks. Silicification is localized by faults and shears, and in many areas, silica has replaced large masses of both the volcanic and granitic rocks. Gold occurs as very small (<10 microns) liberated particles in cavities and along fracture surfaces. Jarosite, goethite, and hematite are present in the siliceous groundmass.

In the Isabella deposit, gold in mineral resources occur as very small (<10 microns) liberated particles in cavities and along fracture surfaces and iron oxide minerals jarosite, limonite, and goethite.

In the Pearl deposit, mineralization is very siliceous, and similar in mineralization to the Isabella material. The silver/gold ratio is higher than Isabella. The gold is contained both as locked and free particles, as native and electrum in an average size of 14 microns. The mineralization is associated with goethite, limonite, jarosite and psilomelane (manganese). Sulfide mineralization occurs beneath the Pearl oxide and mixed mineral resources. The underlying sulfide material contains pyrite, pyrrhotite, galena, sphalerite, chalcopyrite, and silver as polybasite and pyrargyrite.

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Isabella Pearl Mine S-K 1300 Technical Report Summary

Natural weathering and fracture-controlled oxidation of sulfide mineralization causes formation of oxide ore (with low sulfide mineral). Gold is present as free gold, residing in iron oxide minerals or quartz, and adsorbed on clay minerals. Metallurgical test work has determined that gold is amenable to cyanidation and that the oxidized portion of these mineral deposits are metallurgically the same and yield similar metal recovery results when processed.

10.3	Previous Metallurgical Test Work Programs

The Isabella Pearl mine has been subjected to nine separate programs of modern metallurgical test work, the most relevant being the Combined Metals-Homestake joint venture undertaken in 1990, and TXAU in 2009. These two programs are considered of particular interest as the work was performed on drill hole samples and tested for cyanide leachability. There were many other programs where the work focused principally on alternative recovery methods such as flotation. Nonetheless, all cyanide leachability data from all test programs along with that completed by WLMC during 2017 was considered in the conclusions presented herein. A breakdown of the test work, including a study commissioned by WLMC in 2017, are summarized in Table 10-1 below:

Table 10-1 : Summary Metallurgical Test Work Completed on Isabella Pearl Deposit


	Test Program
Report Date	Laboratory	Bottle Roll	Column Leach	Other Tests
16-May-83	Kappes Cassiday & Associates	6	0	100M to 1/2 inch cyanidation
15-May-89	Dawson Metallurgical Laboratories	6	0	100M to 1/4 inch cyanidation
8-Dec-89	Dawson Metallurgical Laboratories	38	0	Agitated leach and flotation test work, 21 oxide and 8 sulfide core samples
10-Jan-90	McClelland Laboratories	2	4	Mechanically agitated leach and Vat leach test work. Column leach at 4 inch crush size
1-Feb-90	Cosatech	0	0	Bioleach test work
20-Jan-92	Hazen Research	0	0	Agitated leach on 10M sulfide ore
8-Oct-97	Kappes Cassiday & Associates	0	0	Flotation test work on 4 sulfide samples
29-Jun-09	McClelland Laboratories	17	2	ADR & heap drain down test work
8-Feb-17	Kappes Cassiday & Associates	8	4	Head grade and screen analysis, QXRD clay identification, shake, bottle and column leach on 1/2" crush.

For details of previous metallurgical test work programs, the reader is referred to earlier reports on mineral resources and reserves and the feasibility study for the Isabella Pearl mine (Brown et al, 2018, 2021; Hulse et al, 2022). The most relevant results of these programs were those completed by Combined Metals-Homestake joint-venture and TXAU, both of which tested for the application of Heap Leach and the ADR process to Isabella Pearl mineral resources. The TXAU metallurgical program was completed on

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DDH and a bulk surface sample. A complete description of this test work can be found in the report by MDA (Prenn and Gustin, 2013). The combined results of all the bottle roll tests and column tests completed, it can be concluded that:

●

There is very good repeatability between samples of any given particle size.

●

Gold recovery for the finer size (200 mesh) was between 86% and 95% except for one sample which had 2.7% contained sulfide.

●

At coarser particle size (>10 mm) gold recovery ranged from 64% to 89%.

●

Column leach tests performed on P100 5/8 inch showed high gold recovery.

10.4	WLMC Metallurgical Ore Characterization Test Work Programs

The basis of the latest WLMC metallurgical test program undertaken by KCA in February 2017 (KCA, 2017) was the clear definition of the metallurgical characteristics of the remaining ore reserves at Isabella Pearl. There were two main objectives:

Confirm previous cyanide leach test work results and viability of Heap Leach, Carbon Adsorption/desorption, and Electrowinning gold recovery process to the Oxide mineral resources.

Establish that the high-grade core of the Pearl deposit would indeed yield previously determined, gold recovery levels.

The program consisted of a PQ size DDH program consisting of 4 holes, in October and November of 2016, totaling 735 meters. Four samples for metallurgical testing were taken from 3 of these holes: IPDD-001 (2 sample intervals), IPDD-003 (1 sample interval) and IPDD-004 (1 sample interval). The metallurgical samples were sent to the KCA metallurgical testing facility in Reno. The main purpose of the test work program was to confirm that the high-grade core zone of the Pearl deposit indicates economic gold recovery as demonstrated in earlier work by others. Two holes intercepted the Pearl deposit, and one was drilled in the Isabella deposit. Figures 10.1 and 10.2 present the plan and section of the DDH holes completed by WLMC in late 2016 (Note: Hole IPDD-002 was a twin hole of IPDD-001 drilled for geology and assay information). Table 102 below presents the results the gold and silver values of the composites used in the metallurgical test program.

A total of 61 boxes of uncut DDH core representing 1,439 kilograms of material was delivered to KCA laboratories in Reno for sample preparation and testing. The work completed consisted of head analysis (including, whole rock and QXRD), screen analysis by size fraction, comminution, bottle roll, agglomeration, and column leach testing.

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Figure 10-1 : Drill Hole Locations for 2017 WLMC Metallurgical Samples

Figure 10-2 : Section of Sample Locations for WLMC Test Program in Relation to Ore Zone

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Table 10-2 : Summary of Isabella Pearl Mine Core Composites Assays, KCA 2017 Program

KCA Sample No.	Description	Deposit	Assay 1, Au g/t	Assay 2, Au g/t	Avg. Assay, Au g/t
76584 B	IPDD-001, 240.5' to 320.5'	Pearl	0.0274	0.024	0.0257
76585 B	IPDD-001, 320.5' to 469.5'	Pearl	1.2651	1.248	1.2566
76586 B	IPDD-003, 219.5' to 422.0'	Pearl	9.2743	9.3257	9.3
76587 B	IPDD-004, 0.0' to 211.0'	Isabella	0.744	0.7509	0.7474

KCA Sample No.	Description	Deposit	Assay 1, Ag g/t	Assay 2, Ag g/t	Avg. Assay, Ag g/t
76584 B	IPDD-001, 240.5' to 320.5'	Pearl	0.411	0.411	0.411
76585 B	IPDD-001, 320.5' to 469.5'	Pearl	2.811	3.017	2.914
76586 B	IPDD-003, 219.5' to 422.0'	Pearl	58.8	59.211	59.006
76587 B	IPDD-004, 0.0' to 211.0'	Isabella	3.189	3.394	3.291

Notes:

The detection limit for silver with FAAS finish is 0.006 opst.

Note - For the purpose of calculation a value of 1/2 the detection limit is utilized for assays less than the detection limit.

10.4.1

Results of WLMC Metallurgical Test Drill Hole Samples

10.4.1.1

Head Screen Analysis

Head screen analysis was carried out on portions of each of the four sample composites at the as received crush sizes. The objective of the head screen analysis was to determine assay grade values from select crush size fractions.

A summary of the head screen analyses is presented in Table 103. The head screen analyses detail is presented in Table 104 and shown graphically in Figure 103.

Table 103 Summary of Head Screen Analyses

Description	Calc p80 Size, inches	Weighted Avg. Head Assay, Au gpt	Weighted Avg. Head Assay, Ag gpt	% Passing 10 mesh	% Passing 100 mesh	% Passing 200 mesh
IPDD-001, 240.5' to 320.5'	0.170	0.021	0.343	62.6%	19.2%	15.9%
IPDD-001, 320.5' to 469.5'	0.419	1.258	3.291	40.4%	18.6%	15.8%
IPDD-003, 219.5' to 422.0'	0.657	8.414	53.383	38.3%	23.7%	21.4%
IPDD-004, 0.0' to 211.0'	0.489	0.617	3.600	22.2%	6.7%	5.2%

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Table 10-4 : Detailed Results of Head Screen Analysis

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Figure 10-3 : Head Screen Analysis Showing Cumulative Weight Percent Passing Crush Size (in inches)

In summary, the head screen analysis on the four samples exhibit similar distribution curves. The highest-grade sample IPDD-003 contained the most gold in the finest fraction as compared to the others.

Head analyses for mercury were also conducted utilizing cold vapor/atomic absorption methods. Total copper analyses were conducted utilizing inductively coupled argon plasma-optical emission spectrophotometer (ICAP-OES) as well as by fire assay – atomic adsorption (FA-AA) methods.

The results of the mercury and copper analyses are presented Figure 105.

Table 10-5 : Summary of Mercury and Copper in Sample, KCA 2017 Program

Description	Total Mercury, mg/kg	Total Copper, mg/kg	Cyanide Soluble Copper, mg/kg	Cyanide Soluble Copper, %
IPDD-001, 240.5' to 320.5'	0.04	9	1.04	12%
IPDD-001, 320.5' to 469.5'	0.07	10	4.58	46%
IPDD-003, 219.5' to 422.0'	0.04	21	7.46	36%
IPDD-004, 0.0' to 211.0'	0.05	16	3.50	22%

Head analyses for carbon and sulfur were also conducted utilizing a LECO CS 230 unit. In addition to total carbon and sulfur analyses, speciation for organic and inorganic carbon and speciation for sulfide and sulfate sulfur, were conducted. The results of the carbon and sulfur analyses are presented in Figure 104.

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Table 10-6 : Summary of Carbon and Sulfur Content, KCA 2017 Program

Description	Total Carbon, %	Organic Carbon, %	Inorganic Carbon, %	Total Sulfur, %	Sulfide Sulfur, %	Sulfate Sulfur, %
IPDD-001, 240.5' to 320.5'	0.02	0.02	<0.01	0.06	<0.01	0.06
IPDD-001, 320.5' to 469.5'	0.02	0.02	<0.01	3	2.47	0.53
IPDD-003, 219.5' to 422.0'	0.05	0.04	0.01	2.45	0.83	1.62
IPDD-004, 0.0' to 211.0'	0.02	0.02	<0.01	0.16	0.16	0.11

10.4.1.2

Cyanide Bottle Roll Tests

Table 107 and Table 108 present the gold and silver recovery results of the four 96-hour bottle roll tests completed on 1,000-gram samples that were pulverized to a p80 size of 200 mesh Tyler. Figure 104 and Figure 105 show the graphical results of gold and silver extraction during the leach period for the metallurgical test samples.

In all samples tested leach kinetics were rapid, samples IPDD-003 and IPDD-004 achieved plus 93% of the total metal recovery in 2 hours. Sample IPDD-001 #1 had a low gold head grade of, 0.025 g/t Au and is therefore classified as waste. Sample IPDD-001 #2 contained 2.47% sulfides, its gold recovery did not surpass 62%.

Table 10-7 : Summary Direct Agitated Cyanidation (Bottle Roll) Gold Test Results, KCA 2017 Program


				Bottle Roll Test Results Gold
Description	Zone	Type	Initial pH	Head Average gpt	Calculated Head gpt	Extracted gpt	Avg. Tails, gpt	Au Extracted, %	Leach Time, hours	Final pH	Consumption NaCN, lbs/st	Addition Ca(OH)2, lbs/st
IPDD-001, 240.5' to 320.5'	Pearl	Pulverized	6.6	0.023	0.025	0.011	0.009	41%	96	11	0.28	5.50
IPDD-001, 320.5' to 469.5'	Pearl	Pulverized	4	1.140	1.145	0.757	0.389	66%	96	10	3.95	15.00
IPDD-003, 219.5' to 422.0'	Pearl	Pulverized	5.2	8.437	8.625	8.021	0.607	93%	96	11	1.48	5.50
IPDD-004, 0.0' to 211.0'	Isabella	Pulverized	6.5	0.678	0.619	0.543	0.078	88%	96	11	0.53	3.00

Table 108 Summary Direct Agitated Cyanidation (Bottle Roll) Silver Test Results, KCA 2017 Program


				Bottle Roll Test Results Gold
Description	Zone	Type	Initial pH	Head Average gpt	Calculated Head gpt	Extracted gpt	Avg. Tails, gpt	Au Extracted, %	Leach Time, hours	Final pH	Consumption NaCN, lbs/st	Addition Ca(OH)2, lbs/st
IPDD-001, 240.5' to 320.5'	Pearl	Pulverized	6.6	0.373	0.280	0.103	0.187	36%	96	11	0.28	5.50
IPDD-001, 320.5' to 469.5'	Pearl	Pulverized	4	2.644	2.768	1.871	0.902	67%	96	10	3.95	15.00
IPDD-003, 219.5' to 422.0'	Pearl	Pulverized	5.2	53.53	54.244	28.466	25.785	52%	96	11	1.48	5.50
IPDD-004, 0.0' to 211.0'	Isabella	Pulverized	6.5	2.986	3.141	1.951	1.182	62%	96	11	0.53	3.00

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Figure 10-4 : Bottle Roll Tests Showing % Gold Extraction During Leach Period

Figure 10-5 : Bottle Roll Tests Showing % Silver Extraction during Leach Period

10.4.1.3

Agglomeration Test Work

Preliminary agglomeration test work was conducted on portions of the crushed material. For the test work, the material was agglomerated with various additions of lime or cement. In the preliminary agglomeration testing, the agglomerated material was placed in a column with no compressive load and then tested for permeability. The purpose of the percolation tests was to examine the permeability of the material under various cement agglomeration levels. The percolation tests were conducted in small (3

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inch inside diameter) columns at a range of cement levels with no compressive load applied. Two (2) tests (KCA Test Nos. 77513 F and 77513 J) failed the parameters utilized by KCA due to excessive pellet breakdown. All other tests passed the KCA parameters. However, it should be noted that the IPDD-001, 320.5’ to 469.5’ sample (KCA Sample No. 76585 B) showed overall low pH values. Once the agglomeration test work was complete, it was decided that the IPDD-003, 219.5’ to 422.0’ material should be agglomerated with cement (KCA Test No. 77517). However, a second column was run with the same material without cement agglomeration (KCA Test No. 77565). The flow rates and percent (%) slump observed in the non- agglomerated column were similar to the agglomerated column. A comparison of the drain down values and % slumps of the column leach tests on IPDD-003, 219.5’ to 422.0’ material is presented in Table 109.

Table 109 : Bureau Veritas vs ALS Gold Assay Comparison Plot

KCA Sample No	KCA Test No	Description	96hour Drain Down, Gallons H20/ stdry ore	Slump %
76586 B	77517	IPDD-003, 219.5' to 422.0'	10.9	0.3%
76586 B	77565	IPDD-003, 219.5' to 422.0'	9.4	0.4%

10.4.1.4

Column Leach Test Work

The crushed material split out for column test work was blended with lime or agglomerated with cement as necessary and then loaded into a 4-inch diameter plastic column. Alkaline cyanide solution was continuously distributed onto the material through Tygon tubing. The flow rate of solution dripping onto the material was controlled with a peristaltic pump to 0.004 to 0.005 gallons per minute per square foot of column surface area.

After each cycle the solution was passed through activated carbon over a period of 24 hours to extract the gold and silver in solution. After passing through the bottle of activated carbon, the solution was re-assayed for pH, NaCN, Au and Ag. Sodium cyanide was then added, if necessary, to maintain the solution at "target" levels. The leach solution was then recycled to the material for another 24-hour leach period. Two (2) batches of leach solution were used so that while one batch was applied to each column, the other was run through carbon.

Three (3) column leach tests were conducted utilizing material crushed to 100% passing ⅝ inches (IPDD-001, 320.5’ to 469.5’, IPDD-003, 219.5’ to 422.0 and IPDD-004, 0.0’ to 211.0’). During testing, the material was leached for 46 days with a sodium cyanide solution. Additionally, a column leach test was conducted utilizing material crushed to 100% passing ⅝ inches. During testing, the material was leached for 28 days with a sodium cyanide solution. The material in the column was then washed for 30 days.

The column leach test results exhibited rapid leach kinetics. The highest-grade sample IPD-003 grading 9.3 g/t Au was tested twice, first under agglomeration and then without agglomeration, both results achieved gold recovery of 88% and 89% in 46 and 28 days respectively. Sample IDD-001 grading 1.25 g/t Au and 2.47% sulfide reached a gold recovery of 62% after 46 days. Sample IPDD-004 grading 0.74 g/t Au

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achieved 76% recovery after 46 days. The results of the column leach test work are presented in Table 1010 and shown graphically in Figure 106.

Table 10-10 Summary Column Leach Test Results, KCA 2017 Program

Figure 10-6 : Column Leach Test Results Showing Cumulative Weight Percent Gold Extracted Over Days of Leach

10.5	Discussion of Metallurgical Test Gold Recovery Curves

10.5.1

Discussion of Bottle Roll Test Recovery Curves

Table 1011Table 1016 is a summary of all bottle roll tests completed on Isabella Pearl mine. These results present the very strong relationship between gold recovery and nominal particle size that is subjected to cyanidation. The relationship clearly demonstrates that the more work that is done on the mineral resources that is to be leached, i.e., crushing and grinding the greater the fines fraction, the greater the quantity of economic minerals to be liberated the greater the recovery and faster the recovery rate. This

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may be attributed to their very fine nature of the mineral grains and their encapsulation of gold within silica and weathering or oxidation resistant gangue minerals.

Table 10-11 Summary of All Bottle Roll Tests Completed on the Isabella Pearl Mine

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10.5.2

Discussion of Column Leach Test Gold Recovery Curves

All 6 column leach tests performed on core samples from the Isabella Pearl mine are summarized in Table 1012. The NaCN and Lime Consumption during the column leach tests are summarized in Table 1013. Figure 107 presents column leach gold recovery curves for the 6 column leach tests.

The nature of the fast leach kinetics was recorded on every test, with 80 to 90 percent of total recovery occurring in the first 10 days of leaching.

Table 10-12 Summary of All Column Leach Tests Completed on the Isabella Pearl Mine

Table 10-13 : Summary of NaCN and Lime Consumption for the Column Leach Tests

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Figure 10-7 : Column Leach Gold Recovery Curves for Column Leach Tests Completed

10.6	Process Selection and Design Parameters

Cyanidation test work (bottle roll and column leach), performed on representative mineral resources, confirms the close relationship between particle size and gold recovery. The greater the fines fraction the higher the gold recovery. The results of all bottle roll and column leach tests performed are summarized by size fraction and presented in Table 1014 and Table 1015 below.

Table 10-14 : Bottle Roll Gold Recovery Estimate by Size Fraction

Table 10-15 : Column Leach Gold Recovery Estimation by Size Fraction

Interpreting these results, it was observed that:

●

A high level of gold recovery (plus 90 percent) could be achieved using a grinding and milling process. The capital cost and economics of milling, however, is prohibitive given the limited amount of mineral resources, leaving the most viable option to be a heap leach process with a carbon absorption/desorption and electrowinning given low silver to gold ratio.

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●

There exists a marked increase in gold recovery by decreasing the average size fraction of the mineral resources. Review of the combined gold recovery by bottle roll and column leach testing, determined that sizing the material to a p100 of 5/8 inch could reasonably expect a 25% increase in gold recovery (60 to 85%) over ROM size material.

●

Based on the metallurgical test work completed, the recoveries presented in Table 1016 are being used for the mine. Total gold recovery is expected over a four-month period. Considering the economic parameters used in the feasibility study, mineral resources above 0.61 g/t Au are currently being crushed to P80 of 5/8 inch and material between 0.33 and 0.61 g/t Au is being sent to a low-grade stockpile for either future crushing or direct placement on the heap as ROM. Total predicted gold recovery is 81% for all ore. Cement is added to crushed material for pH control. No material is currently agglomerated.

Table 10-16 : Gold Recovery Estimate

Cyanide consumption is expected to average 0.75 kg/t (1.50 lb/ton) of leach material and lime consumption is estimated to average 3.0 kg/t (6.0 lb/ton) of leach material (Table 1017).

Table 10-17 : NaCN and Lime Consumption

Material	Gold Recovery	NaCN Consumption	Lime Consumption
ROM	60 %	0.75 kg/t	6.0 kg/t
5/8 Crush	81 %	0.75 kg/t	6.0 kg/t

10.7	Metallurgical Summary

In summary, lab test work is completed in a static state whereas production is in a dynamic state. Test work of the Isabella Pearl mine deposit samples are completed in column tests in a controlled environment and indicate ideal results.

Production heap leach is performed in a dynamic state where the ore is partially leached, then new ore is stacked above the previous lift, and placed under leach again. Once mining is complete the heap leach will continue to leach gold ounces. Based on the feasibility study column test work the estimated LOM achievable is 81% gold recovery.

Through December 2022, the mine has placed 224,834 gold ounces on the leach pad and has recovered 128,119 gold ounces. This includes gold ounces recovered from the overliner, ROM at beginning of mine life, and crushed ore. As of December 31, 2022, 57.0% of the gold placed has been recovered (Figure 108).

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Figure 10-8 : Graph of Gold Ounces Placed vs. Gold Ounces Poured and Percent Gold Recovery

The Isabella Pearl mine lab has confirmed fast gold extraction in 2021 and 2022 Pearl column leach tests which are also noted in the Report of the Estimates of Reserves and Feasibility Study for the Isabella Pearl Project (December 31, 2017). Final gold extractions of the 2022 Pearl crusher column leach tests varied from 74-82%, which is in line with the 81% estimated recovery shown in the Feasibility Study. Over the life of mine the gold ounces produced should achieve the estimated 81% feasibility study recovery.

Column test reagent consumptions correlated to predicted, 0.75 kg/t NaCN and 6.0 kg/t lime. The 2021 and 2022 Pearl crusher column leach tests NaCN consumptions were noted at 0.10 to 0.32 kg/ton NaCN

Sodium Cyanide consumption during 2022 was 0.89 lb/ton (0.45 kg/t) vs 1.5 lb/ton (0.75 kg/t), closely reflecting consumption rates stated in the feasibility study.

10.7.1

Opinion on Adequacy

The Qualified Persons have reviewed these results. The on-going column testing supports the planned metal recovery as well as the planned cyanide consumption. The comparison of feasibility results with continuous testing of mined ore demonstrates that the earlier work was representative of the deposit and the Qualified Persons consider that these data are appropriate and adequate for estimation of mineral reserves.

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Mineral Resource Estimate

11.1	Introduction

The modeling and estimation of mineral resources presented herein is based on technical data and information available as of December 31, 2022. WLMC models and estimates mineral resources from available technical information prior to the generation of mineral reserves. This estimate was prepared to comply with SEC regulations 17 CFR Subpart 229.1300 Regulation S-K, generally known as the “SK-1300” rule.

Modeling and estimation of mineral resources were carried out using the commercially available Maptek Vulcan software program, version 12.

Any statements and opinions expressed in this document are given in good faith and in the belief that such statements and opinions are true as of the effective date of this report.

11.2	Mineral Resources Definitions

According to S-K 1300, a mineral resource is a concentration or occurrence of material of economic interest in or on the Earth's crust in such form, grade or quality, and quantity that there are reasonable prospects for economic extraction. A mineral resource is a reasonable estimate of mineralization, considering relevant factors such as cut-off grade, likely mining dimensions, location or continuity, that, with the assumed and justifiable technical and economic conditions, is likely to, in whole or in part, become economically extractable. It is not merely an inventory of all mineralization drilled or sampled.

Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no guarantee that all or any part of the mineral resource will be converted into mineral reserve. Confidence in the estimate of Inferred mineral resources is insufficient to allow the meaningful application of technical and economic parameters.

11.2.1

Inferred Mineral Resources

An Inferred mineral resource is that part of a mineral resource for which quantity and grade or quality are estimated based on limited geological evidence and sampling. The level of geological uncertainty associated with an inferred mineral resource is too high to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability. Because an inferred mineral resource has the lowest level of geological confidence of all mineral resources, which prevents the application of the modifying factors in a manner useful for evaluation of economic viability, an inferred mineral resource may not be considered when assessing the economic viability of a mining project and may not be converted to a mineral reserve.

11.2.2

Indicated Mineral Resources

An Indicated mineral resource is that part of a mineral resource for which quantity and grade or quality are estimated on the basis of adequate geological evidence and sampling. The level of geological certainty associated with an indicated mineral resource is sufficient to allow a qualified person to apply modifying

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factors in sufficient detail to support mine planning and evaluation of the economic viability of the deposit. Because an indicated mineral resource has a lower level of confidence than the level of confidence of a measured mineral resource, an indicated mineral resource may only be converted to a probable mineral reserve.

11.2.3

Measured Mineral Resources

A measured mineral resource is that part of a mineral resource for which quantity and grade or quality are estimated on the basis of conclusive geological evidence and sampling. The level of geological certainty associated with a measured mineral resource is sufficient to allow a qualified person to apply modifying factors, as defined in this section, in sufficient detail to support detailed mine planning and final evaluation of the economic viability of the deposit. Because a measured mineral resource has a higher level of confidence than the level of confidence of either an indicated mineral resource or an inferred mineral resource, a measured mineral resource may be converted to a proven mineral reserve or to a probable mineral reserve.

11.3	Database

Mineral resources described in this report are gold and silver bearing material that have been physically delineated by one or more methods including drilling, surface mapping, and other types of sampling. This material has been found to contain sufficient mineralization of an average grade to have potential that warrants further exploration evaluation. This material is reported as mineral resources only if the potential exists for reclassification into the mineral reserves category. Mineral resources cannot be classified in the mineral reserves category until technical, economic, and legal factors have been evaluated.

The modeling and estimation reported herein utilized the drill hole database compiled by WLMC. Drill holes with assay samples within the immediate mine area were imported into a Maptek Vulcan database. The extracted drill hole database contains 596 unique collar records (Table 11.1) and 34,936 assay records, broken down by drilling type as:

●

AT: 6 drill holes for 82.0 m (269 ft)

●

RC: 554 drill holes for 53,317.2 m (174,925 ft)

●

DDH: 36 drill holes for 3,564.4 m (11,695 ft)

Industry standard validation checks of the database were carried out with minor corrections made where necessary. The database was reviewed for inconsistencies in naming conventions or analytical units, duplicate entries, interval, length, or distance values less than or equal to zero, blank or zero-value assay results, out-of-sequence intervals, intervals, or distances greater than the reported drill hole length, inappropriate collar locations, and missing interval and coordinate fields. No significant discrepancies with the data were noted.

Drill hole distance units are reported in meters and grade units are reported as either g/t or ppm. The collar coordinates were provided in the WGS 1984 UTM Zone 11N coordinate system. The observed nearest neighbor collar mean distance is 13.4 (44 ft) m. The Isabella Pearl drill hole and assay databases

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are summarized in Table 111 and Table 112, respectively. Summary statistics were also tabulated for the assay data (Table 113).

Table 11-1 Isabella Pearl Drill Hole Database Summary

Description	DDH	RC	AT	Historical	Total
Number of Drill Holes	36	554	6	13	609
Total Length (m)	3,564.4	513,317.2	82.0	1,586.5	58,550.1
Average Length (m)	99.0	96.2	13.7	122.0	96.1
Meters Assayed	1,950.6	49,885.3	82.0	1,575.8	53,493.7
Drill Holes with Downhole Surveys	11	349	6	13	379

Table 11-2 : Isabella Pearl Assay Database Summary

Assay Summary	DDH	RC	AT	Historical	Total
Number of Au Assays	1,119	32,729	54	1,034	34,936
Total Length (m)	1,950.6	49,885.3	82.0	1,575.8	53,493.7
Average Length (m)	1.74	1.52	1.52	1.52	1.53
Average Au g/t	2.30	0.22	0.30	0.13	0.29
Average Ag g/t	1.85	2.96	1.04	0.77	2.85

Table 11-3 : Isabella Pearl Assay Statistics Summary

Assay Data	Length m	Au ppm	Ag ppm
Mean	1.53	0.29	3.17
Median	1.52	0.01	0.10
Mode	1.52	0.00	0.05
Standard Deviation	0.16	1.85	26.09
CoV	0.10	6.43	8.23
Minimum	0.0001	0.0001	0.0001
Maximum	7.93	106.52	1,923.00
Count	34,942	34,936	33,571

The Isabella Pearl assay database (Table 112) indicates that the mean gold grades of the DDH holes are significantly higher than the RC holes. The Combined Metals-Homestake and TXAU DDH were drilled primarily to collect metallurgical samples and verify important mineralized zones defined by previously drilled RC holes. The DDH therefore drilled a higher percentage of mineral resources than the RC holes, especially in the high-grade Pearl deposit. In addition, sampling of the DDH was primarily restricted to suspected mineralized intervals, while the RC holes were sampled over their entire lengths.

Drill hole logs are available for all holes except IC-1 through 37 (the earliest holes in the database) and IC-54, as well as copies of assay certificates for 147 of the holes, including all TXAU holes. A significant amount of information was collected from the drill logs and entered into spreadsheets and, where appropriate, the mine database, including the depth to water table, intervals drilled while injecting water, the amount of water returning with the RC sample cuttings, qualitative descriptions of RC sample recoveries, any comments regarding possible RC down-hole contamination noted on the drill logs, other comments written on the drill logs that pertain to water and recovery, alteration (degree of silicification), lithology

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(overburden, welded and overlying unwelded Mickey Pass Tuff, granite), drill bit types and diameters, drill contractors, year of drilling, rig type, assay laboratory, analytical methods, and analytical detection limits. Although the database included oxidation codes, many of these codes were derived from the coding of the drill samples by an interpreted three-dimensional surface that conflicted with the oxidation notes in the drill logs in some cases. Oxidation data (oxide-mixed-sulfide) were therefore extracted from the drill logs and incorporated into the MDA digital database.

QA/QC data were also compiled by MDA from the paper copies of the Combined Metals-Homestake assay certificates. These data include internal laboratory check analyses of the original pulps and analyses of new pulps prepared from preparation rejects or duplicate samples.

An audit of the assay database by MDA led to the identification of data in the assay certificates that were not included in the TXAU database. Two RC holes, which had been re-entered and deepened sometime after the original holes were drilled, did not have the re-entry assay data in the database. Several intervals of other holes were also missing assay data. All missing assay data identified by MDA were added to the mine database.

11.3.1

Database Backup

WLMC and FGC company policy includes Windows personal computer folder backup that automatically syncs folders to a OneDrive cloud storage.

11.4	Bulk Density

MDA reported an average bulk density value of 2.20 tonnes per cubic meter (tonnage factor 14.6) for oxidized units and 2.40 tonnes per cubic meter (tonnage factor 13.4) for non-oxidized units in the Isabella Pearl deposit (Prenn & Gustin, 2013). In September 2022, two bulk density measurements for sulfidic waste blast material at the bottom of the Pearl pit averaged 2.44, confirming previous estimates for non-oxidized material.

A total of 38 bulk density measurements were collected by HB Engineering from TXAU geotechnical DDH core, with values ranging from 1.58 tonnes per cubic meter (tonnage factor 20.5) to 3.20 tonnes per cubic meter (tonnage factor 10.0), with a median of 2.21 tonnes per cubic meter (tonnage factor 14.5) and an average value of 2.20 tonnes per cubic meter (tonnage factor 14.6). For the current update, a bulk density of 2.20 tonnes per cubic meter (tonnage factor 14.6) was assigned to the model for oxide material and a bulk density of 2.40 tonnes per cubic meter (tonnage factor 13.4) was assigned to the model for sulfide material, based on the recommendation of the Isabella-Pearl mine engineering department.

RQD data collected by HB Engineering from TXAU geotechnical DDH drill holes also suggests the presence of multiple zones of poor recovery, fractures, and voids (Fig. 111). An additional factor may be required to accommodate the presence of voids and fractured rocks.

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Figure 11-1 : Plot of RQD vs. Elevation

11.5	Wireframe Modeling

11.5.1

Topography

The Isabella Pearl Mine Engineering department supplied a topographic surface based on a high-resolution georeferenced drone survey dated January 1, 2023, for topographic control.

11.5.2

Gridded Surfaces

Gridded surfaces were developed for the oxidation floor and lower granite contact based on logged lithology contacts (Figure 112).

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Figure 11-2 : Isometric View Looking North Showing Oxide Base (blue) and Granite (orange) Contacts

11.5.3

Mineralization Envelopes

Multiple geological structures directly influence the Isabella Pearl mineralization. Vein solids and fault traces were digitized and imported into Vulcan software. Three-dimensional surfaces of the Pearl, Civit Cat and Soda Springs fault, which separate the Mickey Pass Tuff and granitic basement, were created using the digitized fault traces and lithologic drill-hole data. A 3D representation of the colluvium was also generated from surface mapping and drill hole logs.

The Civit Cat North, Crimson, Silica Knob, Isabella, Scarlet North and South, and Pearl domains were modeled based on nominal 0.30 g/t Au (0.009 opst) grade shells using close spaced polygons snapped directly to drill hole assay intervals. To maintain continuity, lower grade assay intervals were incorporated into the modeled domains where appropriate. The interpreted polygons were then consolidated into three-dimensional triangulated wireframes, which were clipped to the updated topographic surface. Modeling of the domains also incorporated blasthole results and geological features exposed during mining, and the Pearl domain has been split into a lower grade “Vein” and higher grade “Main” sub-domain. The resulting mineralization domains were used to back-tag assay and composite intervals and provide reasonable volume constraints (Figure 113).

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Figure 11-3 : Isometric View of the Mineralization Domains comprising the Isabella Pearl Deposit

11.6	Compositing

The average length of assays intervals within the defined mineralization domains is 1.531 m (5.02 ft), with a mode of 1.524 m (5.00 ft) and a median length of 1.524 m (5.00 ft). 99% of the wireframe constrained assays are 1.524 m (5.00 ft) in length (Figure 114). Assays were therefore composited to 1.524 m (5.00 ft) within the defined domains. Residual composite lengths less than 0.762 m (2.50 ft) were merged with the adjacent interval. A small number of missing intervals were treated as nulls.

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Figure 11-4 : Histogram of Constrained Assay Sample Lengths

11.7	Exploratory Data Analysis

Summary statistics were calculated for the composite sample populations (Table 114). The highest average silver grade occurs in the Pearl domain with very low average silver grades in the other domains (Figure 115).

Table 11-4 Wireframe Constrained Composite Statistics

Au g/t	Civit Cat	Crimson	Pearl Main	Pearl Veins	Scarlet South	Silica Knob
Count	411	436	1,088	288	168	150
Average	0.71	0.89	3.59	1.84	0.70	0.58
St Dev	0.64	0.75	6.08	3.91	0.80	0.37
CoV	0.91	0.85	1.69	2.13	1.15	0.65
Minimum	0.0001	0.002	0.0001	0.0001	0.007	0.011
Maximum	5.77	5.14	59.07	31.75	7.65	2.02
Ag g/t	Civit Cat	Crimson	Pearl Main	Pearl Veins	Scarlet South	Silica Knob
Count	411	436	1088	288	168	150
Average	6.80	6.26	46.52	27.51	2.86	3.27
St Dev	13.50	8.98	122.66	58.57	5.61	2.65
CoV	1.99	1.43	2.64	2.13	1.96	0.81
Minimum	0.0001	0.0001	0.0001	0.0001	0.0001	0.05
Maximum	147.79	125.72	1,921.55	468.30	51.30	15.70

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Figure 11-5 : Log-Probability Plots of Au and Ag Composites

The gold sample distributions for RC and DDH composites were also examined for evidence of bias in the Isabella and Pearl mineralization domains. The results suggest that RC drilling is in general slightly undervalued compared to the DDH (DH) drilling at Pearl (Figure 116), which may be due in part to the observed clustering of DDH drilling in the vicinity of the high-grade portion of the Pearl domain.

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Figure 11-6 : RC vs. DDH Drilling Results

A single true twin is available for grade comparison and analysis: IC-145 (a vertical RC drill hole) and IP-DD-002 (a vertical DDH). The separation between collars is 5.97 m (19.58 ft). Both drill holes penetrate the center of the Pearl domain.

Visual comparison of the composite grades between the two drill holes suggests the presence of localized downhole contamination below the oxide base, with elevated grades observed in the RC drill hole compared to the DDH drill hole (Figure 117). Potential contamination in RC drill holes appears to be limited to beneath the oxide base; to accommodate for a potential bias during estimation more restrictive estimation constraints were imposed on the Pearl model.

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Figure 11-7 : Twin Hole Au Assay Grade Comparison

11.8	Treatment of Extreme Values

The potential influence of extreme values during estimation was evaluated by grade capping analysis on the tagged and composited grade intervals. The presence of high-grade outliers was identified by disintegration analysis of the upper tails and examination of histograms and log-probability plots (Figure 118). Composite grades were reduced to the selected threshold prior to estimation. The Pearl capping threshold was then iteratively refined to minimize the relative difference between the resulting average Nearest Neighbor model and block grade estimates (Table 115). For the Pearl Veins, an additional range restriction of 60 m (197 ft) was placed on composites equal to or greater than 50% of the capping threshold.

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Figure 11-8 : Log-Probability Plots of Composite Capping Thresholds

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Table 11-5 Capping Thresholds

Gold	Civit Cat	Crimson	Pearl Main	Pearl Veins	Scarlet S	Silica Knob
Cap (g/t)	4.00	3.00	50.00	10.00	2.00	2.00
Minimum	0.0001	0.002	0.0001	0.0001	0.007	0.011
Maximum	5.77	5.14	59.07	31.75	7.65	2.02
Count	411	436	1088	288	168	150
Number Capped	2	9	4	10	6	1
Uncapped Mean	0.71	0.89	3.59	1.84	0.70	0.58
Capped Mean	0.70	0.87	3.56	1.51	0.63	0.58
Mean Above Cap	5.21	3.81	57.23	19.28	3.84	2.02
Percent Change	-1%	-2%	-1%	-18%	-9%	0%
Silver	Civit Cat	Crimson	Pearl Main	Pearl Veins	Scarlet S	Silica Knob
Cap (g/t)	100	100	250	100	100	100
Minimum	0.0001	0.0001	0.0001	0.0001	0.0001	0.05
Maximum	147.8	125.7	1921.6	468.3	51.3	15.7
Count	411	436	1088	288	168	150
Number Capped	2	1	29	19	0	0
Uncapped Mean	6.80	6.26	46.52	27.51	2.85	3.26
Capped Mean	6.65	6.20	37.35	20.43	2.85	3.26
Mean Above Cap	130.81	125.72	594.09	207.35	NA	NA
Percent Change	-2%	-1%	-20%	-26%	0%	0%

11.9	Continuity Analysis

Continuity analysis was carried out using median indicator variograms derived from composited grade intervals (Table 116). Only poorly defined experimental semi-variograms could be developed, but the variograms do provide information relevant to the definition of search ranges, anisotropy, and classification (Figure 119).

Table 11-6 Experimental Semi-Variograms and Modeled Rotations

Pearl Main	-50 > 350	0 > 260	40 > 350
C0	0.15	0.15	0.15
C1	0.27	0.27	0.27
C2	0.58	0.58	0.58
R2	44	50	10
R3	60	62	20

Pearl Veins	-45 > 025	0 > 295	45 > 025
C0	0.34	0.34	0.34
C1	0.16	0.16	0.16
C2	0.53	0.53	0.53
R2	43	40	10
R3	47	60	20

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Figure 11-9 : Experimental Semi-Variogams

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11.10

Block Model

A rotated block model was established across the mine with the block model limits selected to cover the extent of the mineral resources and accommodate a potential pit shell (Table 117). A parent block size of 5.0 m x 5.0 m x 6.0 m (16.4 ft x 16.4 ft x 19.7 ft) was selected as representative of the pit shell configuration and selective mining unit.

Table 117 Block Model Setup

	Origin	Offset		Block Size	Sub-Cell
X	396,325.914	1760		5	0.5
Y	4,273,503.559	850		5	0.5
Z	1,400.000	462		6	0.5
Rotation			125 degrees

The block model contains variables for Au and Ag grade estimation, bulk density, classification, drill hole spacing and oxidation state. The modeled oxide floor was used to code blocks as either oxide or sulfide.

11.11

Estimation and Classification

Inverse Distance Cubed (“ID3”) and Nearest Neighbor (“NN”) estimates were carried out using capped composites. A minimum of three and a maximum of twelve composites were used for estimation, within a search ellipsoid oriented parallel with each defined structure and extending 120 m (394 ft) x 120 m (394 ft) x 30 m (98 ft). The major and semi-major axes approximate the average strike and dip directions of the mineralization in each of the estimation areas. Based on preliminary mining results and analysis of blasthole grades, the orientation of the Isabella search ellipse was adjusted to impart a slight anisotropy with the principal axis oriented 040 degrees. Both gold and silver were modeled and estimated.

In order to provide a whole-block estimate suitable for open pit mine planning and reserve reporting, the block model was regularized after estimation to a 5.0 m (16.4 ft) x 5.0 m (16.4 ft) x 6.0 m (19.7 ft) whole block estimate by volume inclusion percent and diluted at zero grade. Blocks that intercepted the modeled colluvium were assigned a zero grade.

Classification parameters were derived from the original MDA criteria (Prenn & Gustin, 2013). The most relevant factors used in the classification process were:

●

Drill hole spacing density

●

Level of confidence in the geological interpretation

●

Observed continuity of mineralization

●

Direct proximity to a drill hole

Parent blocks were classified algorithmically by drill hole spacing geometry as follows:

●

A block within 15.0 m (49.0 ft) of a 2008 series DDH drill hole, or the IP-DD-002 DDH drill hole, was classified as a Measured mineral resource. Only blocks within the modeled Pearl domain were classified as Measured mineral resources.

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●

A block was classified as an Indicated mineral resource if five or more composites from at least two drill holes were used for estimation and the nearest composite was within 25.0 m (82.0 ft).

●

All other estimated blocks are classified as Inferred.

An example of a typical cross section showing the drill hole data and modeled mineral-domain envelopes in the most strongly mineralized portions of the Isabella, Pearl and Civit Cat (North) deposits is in Figure 1110.

WLMC is not aware of any environmental, permitting, legal, title, taxation, socio-economic, marketing, political, or other issues that could materially affect the estimation of mineral resources at Isabella Pearl.

Figure 11-10 : Typical Cross-Section Looking NW Showing Gold Grades (g/t) and Classification

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11.12

Mineral Resource Estimate

WLMC models and estimates mineral resources prior to establishing mineral reserves. Mineral resources at Isabella Pearl are further defined by WLMC as mineral resources within a constraining pit shell and above a defined cut-off value. Mineral resources reported herein has been constrained within a Lerchs-Grossman optimized pit shell and are reported at a cut-off grade of 0.33 g/t Au (0.01 opst Au), for oxide material and at a cut-off grade of 2.00 g/t Au (0.058 opst Au) for sulfide material, derived from the unit costs and recoveries discussed in Section 12.6.2. The gold price is based on the average consensus forecast for 2023 through 2024 (CIBC, 2023). Other costs are based on actual Isabella Pearl production costs. The mining method is by open pit extraction and all Measured and Indicated mineral resources within the design pit shell and above cut-off have been converted to mineral reserves.

Measured and Indicated mineral resources reported for Isabella Pearl contain 924,300 tonnes (1,018,900 short tons) of material at an average gold grade of 3.22 g/t Au (0.094 opst Au) and 37 g/t Ag (1.085 opst Ag) (Table 118). Inferred mineral resources reported for Isabella Pearl contain 130,800 tonnes (144,100 short tons) of material at an average gold grade of 1.37 g/t Au (0.040 opst Au) and 12 g/t Ag (0.354 opst Ag).

Mineral resources are reported inclusive of mineral reserves. Oxide mineral resources, and only sulfide mineralization within the Pearl pit pushback, are reported as mineral resources.

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Table 11-8 Mineral Resource Inventory for the Isabella Pearl Deposit, December 31, 2022


Class	Cut-off Au (g/t)	Phase	Tonnes	Short Tons	Au (g/t)	Au (opst)	Ag (g/t)	Ag (opst)	Au (oz)	Ag (oz)
Measured	0.33	Pearl Oxide	374,600	412,900	3.75	0.11	50.1	1.461	45,200	603,100
Measured	2.00	Pearl Sulfide	158,300	174,500	4.96	0.14	58.8	1.715	25,200	299,300
Total Measured	---	---	532,900	587,400	4.11	0.12	52.7	1.536	70,400	902,400

Indicated	0.33	Pearl Oxide	93,300	102,900	2.90	0.08	30.3	0.883	8,700	90,800
Indicated	2.00	Pearl Sulfide	76,400	84,200	4.81	0.14	32.2	0.940	11,800	79,200
Indicated	0.33	Civit Cat	80,500	88,800	0.69	0.02	5.9	0.172	1,800	15,200
Indicated	0.33	Silica Knob	78,400	86,500	0.57	0.02	3.2	0.095	1,400	8,200
Indicated	0.33	Scarlet South	62,700	69,100	0.71	0.02	4.7	0.137	1,400	9,400
Total Indicated	---	---	391,400	431,400	2.00	0.06	16.1	0.470	25,200	202,900
Mea + Ind	---	---	924,300	1,018,900	3.22	0.09	37.2	1.085	95,600	1,105,300

Inferred	0.33	Pearl Oxide	40,900	45,100	2.72	0.08	27.6	0.804	3,600	36,200
Inferred	2.00	Pearl Sulfide	5,300	5,900	3.84	0.11	18.4	0.537	700	3,100
Inferred	0.33	Civit Cat	77,100	85,000	0.57	0.02	4.5	0.130	1,400	11,100
Inferred	0.33	Silica Knob	6,500	7,100	0.44	0.01	2.8	0.082	100	600
Inferred	0.33	Scarlet South	1,000	1,100	0.52	0.02	3.0	0.087	-	100
Total Inf	---	---	130,800	144,100	1.37	0.04	12.2	0.354	5,800	51,100

Notes:

Reported at a cut-off of 0.33 Au g/t (0.01 Au opst) for oxide mineral resources and 2.00 Au g/t (0.058 opst) for sulfide mineral resources.

Whole block diluted estimates reported within an optimized pit shell.

Mineral resources do not have demonstrated economic viability.

Totals may not sum exactly due to rounding.

Mineral resources reported are inclusive of reserves.

11.13

Risk Factors

Relevant factors which may affect the estimation of mineral resources include changes to the geological, geotechnical and geo-metallurgical models, infill drilling to convert material to a higher classification, drilling to test for extensions to known mineral resources, collection of additional bulk density data and significant changes to commodity prices. It should be noted that these and other factors pose potential risks and opportunities, of greater or lesser degree, to the estimate as the model is based on currently available data. Risks associated with key estimation parameters are tabulated in Table 119.

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Table 11-9 : Estimation Risk Factors


Category	Description	Risk	Potential for Adverse Impact
Database	Database Integrity	Assay database is compiled from historical data.	Very Low
Drilling	Technique	6 AT drill holes included in estimate.	Low
Drilling	Technique	Infill drilling and mining have confirmed the model.	Low
Drilling	Contamination	Infill drilling and mining have confirmed the model.	Low
Drilling	Logging	Infill drilling and mining have confirmed the model.	Low
Drilling	Recovery	RQD results show a wide range of recoveries. Blast hole and infill grades confirm model.	Low
Drilling	Data Density	Drill hole spacing is ~ 19 m.	Low
Drilling	Survey	Only 10% of drill holes have downhole surveys.	Low
Geology	Geological Interpretation	Based on drill holes and field mapping.	Low
Geology	Oxide Base	WLMC has completed targeted drilling to determine the base of the oxide zone	Low
Geology	Oxide Zone	CN leach assays have quantified the impact of transitional material.	Low
Model	Estimation	ID3 is used for estimation.	Very Low
Model	Bulk Density	Significant voids may reduce recoverable tonnage. Mining of deeper orebody reduces risk.	Low
Model	Grade Continuity	Infill drilling and mining have confirmed the model.	Low
Model	Economics	Reasonable cutoff grades have been applied.	Low
Sampling	Predominantly 1.52m (5ft) samples	Sample size is based on RC drilling intervals.	Very Low
Sampling	Quality of assay data	WLMC has relied on MDA for quality assessment of historical data.	Low

11.14

Model to Production Reconciliation

Convergent’s QP reviewed the reconciliation data for the period November 2019 to August 2022. Convergent noted local fluctuations where production from specific areas of the deposit was small and where contributions to, or from, the low-grade stockpile occurred, but the overall production weighted

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reconciliations are considered reasonable. The overall weighted reconciliation for the Isabella area is 103%, for Pearl 117% and combined 108%. In other words, the production exceeded the model’s metal prediction by 3%, 17% and 8% respectively.

11.15

Opinion on Adequacy

Convergent considers the WLMC 2022 mineral resource estimate to meet industry standards. In general, the reconciliation performance of the model is correctly predicting the metal production. Convergent considers that the sampling and estimation methodology permit the estimation of Measured and Indicated mineral resource estimates, and sufficient technical information is available to convert Measured and Indicated mineral resources to Proven and Probable mineral reserves.

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Mineral Reserve Estimate

12.1	Introduction

The mineral reserve estimates presented herein were prepared according to the guidelines of Regulation S-K part 1300. The reserve estimate is based on technical data and information available as of December 31, 2022.

12.2	Mineral Reserve Definitions

A mineral reserve is an estimate of tonnage and grade or quality of indicated and measured mineral resources that, in the opinion of the qualified person, can be the basis of an economically viable project. More specifically, it is the economically mineable part of a measured or indicated mineral resource, which includes diluting materials and allowances for losses that may occur when the material is mined or extracted.

12.2.1

Probable Mineral Reserve

A Probable mineral reserve is the economically mineable part of an Indicated and, in some circumstances, Measured mineral resource. It includes diluting materials and allowances for losses which may occur when the material is mined. Appropriate assessments, which may include feasibility studies, have been carried out and include considerations of and modifications by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social, and governmental factors. These assessments demonstrate at the time of reporting that extraction is reasonably justified. A Probable mineral reserve has a lower level of confidence than a Proven mineral reserve.

12.2.2

Proven Mineral Resource

A Proven mineral reserve is the economically mineable part of a Measured mineral resource. It includes diluting materials and allowances for losses which may occur when the material is mined. Appropriate assessments, which may include feasibility studies, have been carried out and include consideration of and modification by realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social, and governmental factors. These assessments demonstrate at the time of reporting that extraction is reasonably justified.

Proven mineral reserve is the economically mineable part of a measured mineral resource and can only result from conversion of a measured mineral resource.

12.3	Previous Mineral Reserve Estimate

A previous estimate of Proven and Probable mineral reserves was released by WLMC with an effective date of December 31, 2021 (Table 121); previous mineral reserves were based on a gold price of $1,738/oz Au. Mineral reserves stated in the table below are contained within and engineered pit design following the $1,738/oz Au sales price Lerchs-Grossman pit.

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Table 12-1 : Mineral Reserve Statement Isabella Pearl Mine, Mineral County, Nevada, as of December 31, 2021


Class	Tonnes	Short Tons	Au g/t	Au opst	Ag g/t	Ag opst	Au Oz	Ag Oz
Proven Mineral Reserves	483,300	532,800	5.26	0.154	47	1.4	81,800	733,100
Probable Mineral Reserves	425,500	469,000	2.04	0.06	16	0.5	27,900	221,000
Proven and Probable Total	908,800	1,001,800	3.75	0.11	33	1	109,700	954,100
High Grade Stockpile	14,000	15,400	10.09	0.295	88	2.6	4,500	39,600
Low Grade Stockpile	435,000	479,500	0.53	0.015	5	0.1	7,300	63,900
Isabella Pearl Mine Total	1,357,800	1,496,700	2.78	0.081	24	0.7	121,500	1,057,600

Notes:

Metal prices used for P&P reserves were $1,738 per ounce of gold and $23.22 per ounce of silver. These prices reflect the consensus 2022-2024 average prices for gold and silver (CIBC, 2021).

The quantities of material within the designed pits were calculated using a cut-off grade of 0. 33 Au g/t.

Mining, processing, energy, administrative and smelting/refining costs were based on 2021 actual costs for the Isabella Pearl mine.

Metallurgical gold recovery assumptions used were 81% for all ore which is currently being crushed. These recoveries reflect predicted average recoveries from metallurgical test programs.

P&P reserves are diluted and factored for expected mining recovery.

Figures in tables are rounded to reflect estimate precision and small differences generated by rounding are not material to estimates

100% of the pit constrained Measured & Indicated mineral resources were converted to reserves.

12.4	Mineral Reserve Estimation

The conversion of mineral resources to mineral reserves is based on modifying factors applied to Lerchs-Grossmann (LG) pit optimization, detailed pit design, scheduling and associated modifying parameters. Detailed access, haulage, and operational cost criteria were applied in this process for each deposit (Isabella, Pearl, Civit Cat North, and Scarlet South). The mine was built in metric units and all metal grades are g/t.

The orientation, proximity to the topographic surface, and geological controls of the Isabella Pearl mineralization support mining of the mineral reserves with open pit mining techniques. To calculate the mineable reserve, pits were designed following an optimized LG pit shell based on a $1,750/oz Au sales price. The production pit design based off of the LG pit shell was evaluated against the sub-blocked model to generate tons and grade. The $1750/oz Au price was chosen to create the primary guide surface based on a price sensitivity and subsequent profitability study that showed that the $1,750 pit maximized profitability while reducing capital requirements. The quantities of material within the designed pits were calculated using a cut-off grade of 0.33 g/t Au which is based on the consensus 2023-2024 average price of $1,750/oz for gold (CIBC, 2023) observed at the time of this mineral reserve reporting.

12.5	Mineral Reserve Estimates

The Isabella Pearl mine open pit mineral reserve statement with an effective date of December 31, 2022, is presented in Table 122, and by deposit, in Table 123.

The Proven and Probable mineral reserves reported for Isabella Pearl contain 0.91 million tonnes (1.01 million short tons) at an average gold grade of 2.02 g/t Au (0.059 opst) and 22 g/t Ag (0.6 opst) (Table 122). The mine mineral reserves are based on a gold price of $1,750/oz Au. Mineral reserves stated in the

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table below are contained within and engineered pit design following the $1,750/oz Au sales price Lerchs-Grossman pit. The high-grade and low-grade stockpiles of ore mined but not processed are included in the inventory of 2022 mineral reserves.

Table 12-2 : Mineral Reserve Estimates for the Isabella Pearl Deposit, Mineral County, Nevada, as of December 31, 2022


Class	Tonnes	Short Tons	Au g/t	Au opst	Ag g/t	Ag opst	Au Oz	Ag Oz
Proven Mineral Reserves	250,400	276,000	4.38	0.128	49	1.4	35,200	392,700
Probable Mineral Reserves	171,500	189,100	1.77	0.052	17	0.5	9,800	92,900
Proven and Probable Total	421,900	465,100	3.32	0.097	36	1.0	45,000	485,600
High-Grade Stockpile	65,300	72,000	3.46	0.101	37	1.1	7,300	78,400
Low-Grade Stockpile	426,500	470,100	0.52	0.015	6	0.2	7,100	76,600
Isabella Pearl Mine Total	913,700	1,007,181	2.02	0.059	22	0.6	59,400	640,600