Note 14 - Segmented Information - Operating Results by Geographic Segments (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Mineral Property Expenditures	$ 1,323,323	$ 899,217	$ 2,846,774	$ 1,765,460
General and administrative	2,394,794	2,183,463	4,709,964	4,442,398
Depreciation, amortization and accretion	81,752	84,807	158,138	173,583
	3,799,869	3,167,487	7,714,876	6,381,441
Loss from operations	(3,799,869)	(3,167,487)	(7,714,876)	(6,381,441)
Other income (expenses)	1,909,276	811,015	780,028	568,375
Loss before income taxes	(1,890,593)	(2,356,472)	(6,934,848)	(5,813,066)
United States Texas [Member]
Mineral Property Expenditures	891,008	575,666	2,045,350	1,154,488
General and administrative	1,713,121	1,508,298	3,413,998	3,070,055
Depreciation, amortization and accretion	72,437	76,327	139,933	156,412
	2,676,566	2,160,291	5,599,281	4,380,955
Loss from operations	(2,676,566)	(2,160,291)	(5,599,281)	(4,380,955)
Other income (expenses)	(844,506)	(775,613)	(1,719,112)	(1,461,146)
Loss before income taxes	(3,521,072)	(2,935,904)	(7,318,393)	(5,842,101)
United States Arizona [Member]
Mineral Property Expenditures	21,600	22,866	46,172	52,987
General and administrative	3,439	3,482	6,828	6,871
Depreciation, amortization and accretion
	25,039	26,348	53,000	59,858
Loss from operations	(25,039)	(26,348)	(53,000)	(59,858)
Other income (expenses)	(4,768)	(4,768)	(9,535)	(9,535)
Loss before income taxes	(29,807)	(31,116)	(62,535)	(69,393)
United States Wyoming [Member]
Mineral Property Expenditures	144,182	147,418	292,225	295,294
General and administrative	20,478	23,132	55,191	54,502
Depreciation, amortization and accretion	3,720	3,720	7,437	7,439
	168,380	174,270	354,853	357,235
Loss from operations	(168,380)	(174,270)	(354,853)	(357,235)
Other income (expenses)	700	100	700	400
Loss before income taxes	(167,680)	(174,170)	(354,153)	(356,835)
United States Other States [Member]
Mineral Property Expenditures	16,614	15,345	36,725	39,220
General and administrative	410	1,687	1,062	1,948
Depreciation, amortization and accretion	249	249	498	498
	17,273	17,281	38,285	41,666
Loss from operations	(17,273)	(17,281)	(38,285)	(41,666)
Other income (expenses)		1,578,864		1,578,864
Loss before income taxes	(17,273)	1,561,583	(38,285)	1,537,198
CANADA
Mineral Property Expenditures		135		15,723
General and administrative	634,315	613,571	1,188,021	1,225,041
Depreciation, amortization and accretion	2,465	2,589	5,054	6,487
	636,780	616,295	1,193,075	1,247,251
Loss from operations	(636,780)	(616,295)	(1,193,075)	(1,247,251)
Other income (expenses)	2,756,714	11,242	2,505,298	457,061
Loss before income taxes	2,119,934	(605,053)	1,312,223	(790,190)
PARAGUAY
Mineral Property Expenditures	249,919	137,787	426,302	207,748
General and administrative	23,031	33,293	44,864	83,981
Depreciation, amortization and accretion	2,881	1,922	5,216	2,747
	275,831	173,002	476,382	294,476
Loss from operations	(275,831)	(173,002)	(476,382)	(294,476)
Other income (expenses)	1,136	1,190	2,677	2,731
Loss before income taxes	$ (274,695)	$ (171,812)	$ (473,705)	$ (291,745)