MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT - Cost and Carrying Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Mineral property interests and plant and equipment
Total mineral property interests and plant and equipment, carrying value	$ 169,950	$ 346,281
Mineral property interests
Mineral property interests and plant and equipment
Cost	207,601	359,845
Less: accumulated depreciation	(80,004)	(58,700)
Carrying value	127,597	301,145
Land
Mineral property interests and plant and equipment
Cost	18,043	17,850
Construction in progress
Mineral property interests and plant and equipment
Cost	6,963	8,408
Plant and equipment
Mineral property interests and plant and equipment
Cost	79,972	73,740
Land, construction in progress and plant and equipment in aggregate
Mineral property interests and plant and equipment
Cost	104,978	99,998
Less: accumulated depreciation	(62,625)	(54,862)
Carrying value	$ 42,353	$ 45,136

Net carrying value of mineral property interests and plant and equipment.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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