MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT - Cost and Carrying Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Mineral property interests and plant and equipment
Total mineral property interests and plant and equipment, carrying value	$ 346,281	$ 342,303
Mineral property interests
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, gross	359,845	344,529
Less: accumulated depreciation	(58,700)	(47,197)
Mineral property interests and plant and equipment, carrying value	301,145	297,332
Land [Member]
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, gross	17,850	8,949
Construction in Progress [Member]
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, gross	8,408	4,078
Plant and equipment
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, gross	73,740	76,887
Land, construction in progress and plant and equipment in aggregate
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, gross	99,998	89,914
Less: accumulated depreciation	(54,862)	(44,942)
Mineral property interests and plant and equipment, carrying value	$ 45,136	$ 44,972

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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