Note 3 - Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2025

Property, Plant and Equipment.

Schedule of Property, plant, and equipment

(In thousands)	March 31, 2025		December 31, 2024
Plant and equipment	$	367,108	$	331,899
Mining property and mineral rights		120,532		120,532
Construction in process		12,316		31,048
Capitalized mine development costs		210,364		199,595
Less: accumulated depreciation, depletion, and amortization		(222,448)		(201,055)
Total property, plant, and equipment, net	$	487,872	$	482,019

Schedule of Depreciation, depletion, and amortization

	Three months ended March 31,
(In thousands)	2025		2024
Depreciation of plant and equipment	$	10,365	$	8,820
Amortization of right of use assets (finance leases)		1,892		2,493
Amortization and depletion of capitalized
mine development costs and mineral rights		5,285		3,906
Total depreciation, depletion, and amortization	$	17,542	$	15,220