Property, Plant and Equipment, Net (Tables)

3 Months Ended

Mar. 31, 2017

Property, Plant and Equipment, Net

Schedule of components of property, plant and equipment

	March 31,		December 31,
	2017		2016
	(in thousands)
Mineral properties	$	9,352	$	9,352
Exploration properties		2,518		2,518
Royalty properties		200		200
Buildings		4,386		4,386
Mining equipment and machinery		16,067		16,351
Other furniture and equipment		952		952
Asset retirement cost		865		992
		34,340		34,751
Less: Accumulated depreciation and amortization		(25,448)		(25,516)
	$	8,892	$	9,235