Mineral Properties and Development Costs	12 Months Ended
Dec. 31, 2012
Extractive Industries [Abstract]
Mineral Properties, Development Costs and Exploration Rights	Mineral Properties, Development Costs and Exploration Rights Mineral properties and development costs, which are referred to collectively as mineral properties, include acquisition costs, drilling costs, and the cost of other development work, all of which are capitalized. The Company began depleting mineral properties in 2012 using the units of production method over estimated proven and probable reserves. For the year ended December 31, 2012, the Company capitalized a nominal amount of depletion costs in work-in-process inventory related to the reserves that were mined and crushed during that period. Exploration rights represent acquired rights to explore properties that are believed to potentially contain mineral deposits. During the fourth quarter of 2012, the Company completed an acquisition of exploration rights for a total consideration of $16.2 million, which was paid for by the issuance of 788,410 shares of common stock at $10.147 per share and a cash payment of $8.2 million. The Company capitalized these exploration rights at their fair value at the acquisition date as an individual asset purchase.

Mineral Properties, Development Costs and Exploration Rights

Mineral properties and development costs, which are referred to collectively as mineral properties, include acquisition costs, drilling costs, and the cost of other development work, all of which are capitalized. The Company began depleting mineral properties in 2012 using the units of production method over estimated proven and probable reserves. For the year ended December 31, 2012, the Company capitalized a nominal amount of depletion costs in work-in-process inventory related to the reserves that were mined and crushed during that period.

Exploration rights represent acquired rights to explore properties that are believed to potentially contain mineral deposits. During the fourth quarter of 2012, the Company completed an acquisition of exploration rights for a total consideration of $16.2 million, which was paid for by the issuance of 788,410 shares of common stock at $10.147 per share and a cash payment of $8.2 million. The Company capitalized these exploration rights at their fair value at the acquisition date as an individual asset purchase.