MINING IN COLORADOU.S. GEOLOGICAL SURVEY. George Otis Smith. Director. Professional Paper 138. MINING IN COLORADO. A HISTORY OF DISCOVERY, DEVELOPMENT.precius jams mining in colorado,precius jams mining in colorado,The Mining Industry in Colorado | History ColoradoMar 23, 2011 . The document focuses on the three closely related mining industries-precious and base metals, coal, and industrial metals. The geographic.
precius jams mining in colorado