MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT - Cost and Carrying Value (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Mineral property interests and plant and equipment
Mineral property interests and plant and equipment, carrying value	$ 227,208	$ 210,922
Mineral property interests
Mineral property interests and plant and equipment
Cost	305,642	264,495
Less: accumulated depreciation	(123,427)	(98,752)
Carrying value	182,215	165,743
Land
Mineral property interests and plant and equipment
Cost	15,139	12,884
Construction in progress
Mineral property interests and plant and equipment
Cost	30,134	30,151
Plant and equipment
Mineral property interests and plant and equipment
Cost	77,159	73,633
Land, construction in progress and plant and equipment in aggregate
Mineral property interests and plant and equipment
Cost	122,432	116,668
Less: accumulated depreciation	(77,439)	(71,489)
Carrying value	$ 44,993	$ 45,179

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