Wyoming Mine, Gilman Mining District (Battle Mountain Mining District; Red Cliff Mining District), Eagle County, Colorado, USAi

Regional Level Types
Wyoming Mine	Mine
Gilman Mining District (Battle Mountain Mining District; Red Cliff Mining District)	Mining District
Eagle County	County
Colorado	State
USA	Country

The Wyoming is opened by two tunnels which trend southeast in the limestone. The wall rock is dolomitic limestone with the "zebra" texture developed in places, and contains vugs of dolomite, siderite, and quartz crystals. It is rarely replaced by jasperoid, but commonly decomposes to "dolomite sand." At the time of examination most of the workings were inaccessible because of water and caving. Much of the following information was furnished by Messrs J. M. and R. V. Dismant.

There are numerous faults and fissures in the mine, most of which strike northeast and are vertical or have high dips. Three faults were seen which strike northwest. The dip of any one fault may vary in amount and direction; it may dip northwest in the upper workings and southeast on the lower levels. A few ill-defined, flat-lying, northeastward-dipping faults were observed in the upper· part of the limestone near the base of the porphyry, which seem to dip a little more than the beds. It may be that some of these are bedding faults. The fault zones vary in width from a few inches to 4 feet.

The ore, most of which was oxidized, occurred· in faulted and fissured zones and in flat-lying streaks and pockets as a replacement of the limestone. Remnants of ore showed oxides of iron and rare streaks. of pyrite, galena, and sphalerite. The largest bodies were found above or close to the fissures in the upper beds near or adjacent to the porphyry. These flat ore shoots had an average thickness of less than 18 inches and a maximum of 4 feet. In lateral extent they were very irregular, the largest measuring approximately 150 feet across its greatest dimension. The mineralization in the steeply dipping fissures and faults was not wide, and in places occurred only on one side of the break.