This is a small district in central Calaveras County in the vicinity of the town of Mountain Ranch. It includes the Cave City area.
The district is largely underlain by graphite schist, quartzite, limestone, and thin bodies of mlcose schist. Patches of Tertiary auriferous gravels overlie the bedrock. A few narrow gold-quartz veins, in schist, contain small but sometimes rich ore shoots. The ore contains free gold and abundant sulfides, especially galena.
Lode: Gaston Hill. Placer: Cotton Flat, Foley, Hidden Cave, Humboldt, Mountain Ranch, Rose Hill.
Clark, Lorin, 1954, Geology and mineral deposits of the Colaveritas quadrangle: California Div. Mines Spec. Rept. 40, 23 pp.
Clark, W.B., and Lydon, P.A., 1962, Calaveras County, gold: California Div. Mines and Geology County Rept. 2, pp. 32-93.
Turner, H. W., 1894, Jackson folio: U.S. Geol. Survey Geol. Atlas of the U. S., folio 11,6 pp.