MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT - Cost and Carrying Value (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, carrying value	$ 210,922	$ 169,950
Mineral property interests
Mineral property interests and plant and equipment
Cost	264,495	207,601
Less: accumulated depreciation	(98,752)	(80,004)
Carrying value	165,743	127,597
Land
Mineral property interests and plant and equipment
Cost	12,884	18,043
Construction in progress
Mineral property interests and plant and equipment
Cost	30,151	6,963
Plant and equipment
Mineral property interests and plant and equipment
Cost	73,633	79,972
Land, construction in progress and plant and equipment in aggregate
Mineral property interests and plant and equipment
Cost	116,668	104,978
Less: accumulated depreciation	(71,489)	(62,625)
Carrying value	45,179	42,353
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, carrying value	$ 210,922	$ 169,950

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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