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MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2020 USD ($) $ / oz | Jun. 30, 2020 USD ($)
Mineral property interests and plant and equipment |  |
Impairment charges | $ | $ 83,800 | $ 83,805
Nonrecurring | Level 3 | Gold Bar mine | Weighted Average |  |
Mineral property interests and plant and equipment |  |
Long term gold price (in dollars per ounce) | $ / oz | 1,430 |
Nonrecurring | Level 3 | Gold Bar mine | Discounted Cash Flow | Weighted Average |  |
Mineral property interests and plant and equipment |  |
Discount Rate (as a percent) | 9.00% |
Nonrecurring | Level 3 | Gold Bar mine | Discounted Cash Flow | United States | Weighted Average |  |
Mineral property interests and plant and equipment |  |
Inflation index (as a percent) | 2.00% |

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