Note 3 - Property, Plant and Equipment (Tables)

6 Months Ended

Jun. 30, 2024

Property, Plant and Equipment.

Schedule of property, plant, and equipment, net

(In thousands)	June 30, 2024		December 31, 2023
Plant and equipment	$	309,996	$	290,060
Mining property and mineral rights		120,532		120,532
Construction in process		25,779		13,984
Capitalized mine development costs		182,894		174,260
Less: accumulated depreciation, depletion, and amortization		(164,685)		(139,745)
Total property, plant, and equipment, net	$	474,516	$	459,091

Schedule of depreciation and amortization

	Three months ended June 30,				Six months ended June 30,
(In thousands)	2024		2023		2024		2023
Depreciation of plant and equipment	$	9,069	$	7,661	$	17,890	$	14,428
Amortization of right of use assets (finance leases)		2,883		1,999		5,376		3,881
Amortization and depletion of capitalized
mine development costs and mineral rights		3,927		3,896		7,832		7,098
Total depreciation, depletion, and amortization	$	15,879	$	13,556	$	31,098	$	25,407