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MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT (Tables) | 12 Months Ended
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Dec. 31, 2020
MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT |
Schedule of property and equipment | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | December 31, 2020 |  | December 31, 2019
Mineral property interests, cost | ​ | $ | 314,719 | ​ | $ | 339,374
Less: accumulated depletion | ​ | ​ | (34,601) | ​ | ​ | (28,154)
Mineral property interests, carrying value | ​ | $ | 280,118 | ​ | $ | 311,220
​ | ​ | ​ | ​ | ​ | ​ | ​
Plant and equipment, cost | ​ | ​ | ​ | ​ | ​ | ​
Land | ​ | $ | 8,804 | ​ | $ | 8,746
Construction in progress | ​ | ​ | 2,945 | ​ | ​ | 2,961
Plant and equipment | ​ | ​ | 72,188 | ​ | ​ | 133,014
Subtotal | ​ | $ | 83,937 | ​ | $ | 144,721
Less: accumulated depreciation | ​ |  | (34,943) | ​ | ​ | (37,150)
Plant and equipment, carrying value | ​ | $ | 48,994 | ​ | $ | 107,571
​ | ​ | ​ | ​ | ​ | ​ | ​
Mineral property interests and plant and equipment, carrying value | ​ | $ | 329,112 | ​ | $ | 418,791
Summary of mineral property interests | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Name of Property/Complex |  | State/Province |  | Country |  | 2020 |  | 2019 |
Fox Complex | ​ | Ontario | ​ | Canada | ​ | $ | 17,580 | ​ | $ | 14,627 | ​
Lexam | ​ | Ontario | ​ | Canada | ​ | ​ | 41,595 | ​ | ​ | 41,595 | ​
Los Azules Copper Project |  | San Juan |  | Argentina | ​ | ​ | 191,490 | ​ | ​ | 191,490 | ​
Tonkin Properties |  | Nevada |  | United States | ​ |  | 4,833 | ​ |  | 4,833 | ​
Gold Bar Project |  | Nevada |  | United States | ​ |  | 14,675 | ​ |  | 48,492 | ​
Battle Mountain Complex |  | Nevada |  | United States | ​ |  | 785 | ​ |  | 785 | ​
El Gallo Project |  | Sinaloa |  | Mexico | ​ |  | 3,353 | ​ |  | 3,591 | ​
Fenix Project Properties |  | Sinaloa |  | Mexico | ​ |  | 5,807 | ​ |  | 5,807 | ​
Total mineral property interests | ​ | ​ | ​ | ​ | ​ | $ | 280,118 | ​ | $ | 311,220 | ​
Summary of the quantitative and qualitative information related to the unobservable inputs used in the calculation of the Company's non-recurring Level 3 fair value measurements | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​
​ | ​ | Date of Fair Value Measurement | ​ | Valuation Technique | ​ | Unobservable Input | ​ | Range/ Weighted Average
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Gold Bar Mine | ​ | March 31, 2020 | ​ | Discounted Cash Flow | ​ | Discount Rate | ​ | 9%
​ | ​ | ​ | ​ | ​ | ​ | Long Term Gold Price | ​ | $1,430/oz
​ | ​ | ​ | ​ | ​ | ​ | United States Inflation Index | ​ | 2%

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