Location and History
This is a gold-silver district in the Sweetwater Mountains, in northern Mono County about 15 miles north of Bridgeport. It includes the Silverado and Fryingpan Canyon areas. The area was probably first prospected in the early 1860s, but the principal period of mining activity was 1880 to 1884, when more than $500,000 was produced. Settlements that once existed in the district were Belfort, Monte Cristo, and Star City. Some mining was done in the district again in the early 1900s and 1930s, and there has been some prospecting since.
Geology and Ore Deposits
The district is underlain by various types of granitic rocks and andesite and rhyolite. The gold- and silver-bearing deposits occur in north-trending veins of quartz and silicified breccia that are up to 10 feet thick. The ore contains pyrite, argentite, cerargyrite, and often abundant iron oxides. In places, the ore was high in grade. Ore shoots, with stoping lengths of up to several hundred feet, were mined.
Anglo Mission, Frederick, Kentuck, Longstreet, Montague, Silverado, Star and Great Western, Summers, Tiger.
Eakle, A. S., and Mclaughlin, R. P., 1919, Mono County, Patterson district: California Min. Bur. Rept. 15, pp. 165-166.