Note 3 - Property, Plant and Equipment (Tables)

3 Months Ended

Mar. 31, 2019

Notes Tables

Property, Plant and Equipment [Table Text Block]

	March 31, 2019			December 31, 2018
In thousands
Plant and equipment at cost	$	113,564		$	109,911
Construction in process		16,892			12,066
Capitalized mine development costs		45,784			43,037
Less: Accumulated depreciation and amortization		(19,897	)		(15,809	)
Total property, plant and equipment, net	$	156,343		$	149,205