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MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT- Mineral Properties (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Aug. 25, 2017
Mineral Property Interests |  |  |  |
Mineral property interests | $ 311,220 | $ 309,145 |  |
Amortization of mineral property interests and asset retirement obligations | 25,543 | 16,425 | $ 6,576 |
Black Fox |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 14,627 | 16,365 |  |
Lexam VG Gold |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 41,595 | 41,595 |  |
Los Azules Copper Project |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 191,490 | 191,490 |  |
Gold Bar Project |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 48,492 | 44,131 |  |
El Gallo Project |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 3,591 | 4,139 |  |
Fenix Project Properties |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 5,807 | 5,807 |  |
Battle Mountain Complex |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | 785 | 785 |  |
Tonkin Properties |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests | $ 4,833 | $ 4,833 |  |
Black Fox |  |  |  |
Mineral Property Interests |  |  |  |
Mineral property interests |  |  |  | $ 8,954

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- Definition Mineral properties, net of adjustments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64895-109465 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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