CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Consolidated Net loss	$ (8,071)	$ (8,088)	$ (16,123)
Adjustments to reconcile net loss to net cash used by operating activities:
Depreciation and amortization	265	237	251
Non-cash interest expense	205	224	367
Income realized on lease of water rights	(16)
Stock-based compensation for employees and directors	165	365	(40)
Decrease in deposits, prepaid expenses and other	(25)	61	548
Increase(decrease) in accounts payable and accrued liabilities	(846)	(1,400)	(2,445)
Increase(decrease) in post closure reclamation and remediation costs	11	317	(162)
Loss on Termination of Power Transmission Contract			218
Loss on Extinguishment of Senior Convertible Promissory Notes			971
Net cash used by operating activities	(8,312)	(8,284)	(16,415)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase and development of mining properties, land and water rights	(1,929)	(2,133)	(3,620)
Deposits on property, plant and equipment	(612)	(1,553)	(11,473)
Decrease in restricted cash	3,284	8,436	29,961
Net cash used by investing activities	743	4,750	14,868
CASH FLOWS FROM FINANCING ACTIVITIES:
Stock proceeds, net of issuance costs	5,940	(61)	3,813
Cash contributions returned to POS-Minerals		(828)	(2,268)
Repayment of Long-Term Debt	(165)	(154)	(220)
Net cash used by financing activities:	5,775	(1,043)	1,325
Net (decrease) in cash and cash equivalents	(1,794)	(4,577)	(222)
Cash and cash equivalents, beginning of period	8,470	13,047	13,269
Cash and cash equivalents, end of period	6,676	8,470	13,047
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	(942)	(961)	(1,100)
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Equity compensation capitalized as development	51	35	155
Accrued portion of advance royalties	1,000	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)
Noncash change in deposits on property, plant and equipment	$ 37	$ (7)	$ 74