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MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT (Tables) | 9 Months Ended
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Sep. 30, 2019
MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT |
Schedule of property and equipment | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | September 30, 2019 |  | December 31, 2018
Mineral property interests | ​ | $ | 338,085 | ​ | $ | 326,086
Land | ​ |  | 8,745 | ​ |  | 8,699
Construction in progress | ​ | ​ | 3,520 | ​ | ​ | 74,643
Plant and equipment | ​ | ​ | 131,803 | ​ | ​ | 49,578
Subtotal | ​ | $ | 482,153 | ​ | $ | 459,006
Less: accumulated depreciation | ​ |  | (57,316) | ​ | ​ | (35,127)
Net carrying value | ​ | $ | 424,837 | ​ | $ | 423,879
Schedule of leased assets | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30, 2019
​ |  | Operating lease |  | Finance leases
Leased assets, cost | ​ | $ | 1,167 | ​ | $ | 8,048
Accumulated amortization | ​ | ​ | (441) | ​ | ​ | (864)
Net book value | ​ | $ | 726 | ​ | $ | 7,184

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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(13)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 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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