CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Revenue:
Oxide plant lease		$ 1,637	$ 1,644
Total revenue		1,637	1,644
Costs and expenses:
Oxide plant lease costs		(503)	(537)
Exploration expense		(899)	(534)
El Quevar project expense		(272)	(149)
Velardena shutdown and care and maintenance costs		(489)	(350)
Administrative expense		(1,061)	(1,026)
Stock based compensation		(15)	(65)
Reclamation expense		(51)	(49)
Other operating income, net		1,226	157
Depreciation and amortization		(296)	(188)
Total costs and expenses		(2,360)	(2,741)
Loss from operations		(723)	(1,097)
Other income and (expense):
Interest and other income, net		3	18
(Loss) gain on foreign currency		(15)	6
Loss from operations before income taxes		(735)	(1,073)
Net loss		(735)	(1,073)
Comprehensive loss, net of tax:
Unrealized loss on securities			(52)
Comprehensive loss		$ (735)	$ (1,125)
Net loss per common share — basic
Loss (in dollars per share)		$ (0.01)	$ (0.01)
Weighted average common stock outstanding - basic (in shares)	[1]	91,726,375	89,350,286

[1] Potentially dilutive shares have not been included because to do so would be anti-dilutive.