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MINERAL PROPERTIES AND PROPERTY, PLANT AND EQUIPMENT - Schedule of Summary of Mineral Properties (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Mineral properties, net	$ 328,589		$ 328,589		$ 312,266
Mineral Properties, Gross	335,372		335,372		317,398
Less: accumulated depletion	(6,783)		(6,783)		(5,132)
Depreciation	1,450	$ 1,250	2,790	$ 2,430
Sheep Mountain
Property, Plant and Equipment [Line Items]
Mineral properties, net	34,183		34,183		34,183
Bahia Project
Property, Plant and Equipment [Line Items]
Mineral properties, net	32,613		32,613		32,613
Nichols Ranch ISR Project
Property, Plant and Equipment [Line Items]
Mineral properties, net	25,974		25,974		25,974
Roca Honda
Property, Plant and Equipment [Line Items]
Mineral properties, net	22,095		22,095		22,095
Pinyon Plain
Property, Plant and Equipment [Line Items]
Mineral properties, net	10,764		10,764		9,338
Other
Property, Plant and Equipment [Line Items]
Mineral properties, net	1,687		1,687		1,687
Toliara Project
Property, Plant and Equipment [Line Items]
Mineral Properties, Gross	$ 208,056		$ 208,056		$ 191,508