Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Stockpiles - underground mine	$ 3,968	$ 2,365
Stockpiles - open pit mine	833	414
Leach pad	9,103	376
Concentrates	1,340	1,231
Dore	1,581	1,289
Subtotal - product inventories	16,825	5,675
Materials and supplies	7,306	8,667
Total	24,131	14,342
Low-grade ore stockpile inventory	4,700
Dore
Inventory reserve	478	0
Materials And Supplies [Member]
Inventory reserve	1,264	$ 857
Isabella Pearl Project
Inventory adjustment	$ 2,900

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Dore inventory.

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Leach pad inventory.

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Inventories of ore stockpiles not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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Ore stockpiles - open pit mine

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Ore Stockpiles Underground Mine

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Amount of product inventory total.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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