CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Consolidated Net loss	$ (8,088)	$ (16,123)	$ (10,998)
Adjustments to reconcile net loss to net cash used by operating activities:
Depreciation and amortization	237	251	339
Non-cash interest expense	224	367	29
Stock-based compensation for employees and directors	365	(40)	1,718
Loss on Termination of Power Transmission Contract		218	(1)
Loss on Extinguishment of Senior Convertible Promissory Notes		971
Decrease(increase) in deposits, prepaid expenses and other	61	548	(73)
(Decrease)increase in accounts payable and accrued liabilities	(1,400)	(2,445)	417
(Decrease) in post closure reclamation and remediation costs	317	(162)	(122)
Net cash used by operating activities	(8,284)	(16,415)	(8,691)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase and development of mining properties, land and water rights	(2,133)	(3,620)	(9,510)
Deposits on property, plant and equipment	(1,553)	(11,473)	(752)
Decrease in restricted cash	8,436	29,961	974
Net cash used by investing activities	4,750	14,868	(9,288)
CASH FLOWS FROM FINANCING ACTIVITIES:
Stock proceeds, net of issuance costs	(61)	3,813	(36)
Cash contributions returned to POS-Minerals	(828)	(2,268)
Cash contributions received from POS-Minerals			1,348
Proceeds from unit offering			8,535
Increase in capitalized debt issuance costs			(23)
Repayment of Long-Term Debt	(154)	(220)	(261)
Net cash used by financing activities:	(1,043)	1,325	9,563
Net (decrease) in cash and cash equivalents	(4,577)	(222)	(8,416)
Cash and cash equivalents, beginning of period	13,047	13,269	21,685
Cash and cash equivalents, end of period	8,470	13,047	13,269
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Equity compensation capitalized as development	35	155	443
Accrued portion of advance royalties	500	500	500
Conversion of Senior Convertible Promissory Notes		(2,488)
Non-Convertible Senior Promissory Notes Issued		1,340
Return of Contributions Payable to POS-Minerals		36,000
Reduction in Return of Contributions payable to POS-Minerals		(2,116)
Write off of debt issuance costs		(115)
Loan commitment costs			472
Noncash change in deposits on property, plant and equipment	$ (7)	$ 74	$ (709)