13. INCOME TAXES (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Deferred tax liabilities	$ 0us-gaap_DeferredTaxLiabilities	$ 0us-gaap_DeferredTaxLiabilities
Deferred tax assets:
Allowance for obsolete and slow-moving inventories	864	1,657
Impairment on property, plant and equipment	477,427	479,151
Exploration costs	1,952,990	1,837,025
Repair and maintenance costs	0us-gaap_DeferredTaxAssetsOther	0us-gaap_DeferredTaxAssetsOther
Property, plant and equipment	0	0
Property, plant and equipment under capital leases	0	0
Compensation costs of unexercised stock options	1,427,296	2,053,310
US federal net operating loss	9,692,379	9,272,734
Total deferred tax assets	13,550,956us-gaap_DeferredTaxAssetsGross	13,643,877us-gaap_DeferredTaxAssetsGross
Valuation allowance	(11,119,675)	(11,326,044)
Net deferred tax asset	2,431,281us-gaap_DeferredTaxAssetsLiabilitiesNet	2,317,833us-gaap_DeferredTaxAssetsLiabilitiesNet
Current deferred tax asset	864	1,657
Long-term deferred tax asset	$ 2,430,417	$ 2,316,176

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