Indian Hill is in western Sierra County about 10 miles west of Downieville and just south of the Brandy City district. Much of the production here has come from the Indian Hill and Depot Hill hydraulic mines. These mines were extensively worked from the 1850s to the 1880s, and intermittent development work and mining continued through the 1930s. The Depot Hill mine has been prospected recently. The deposits are on the LaPorte-Brandy City Tertiary channel. The lower gravels contain abundant quartz and are as much as 100 feet thick. They are overlain in places by inter-volcanic gravels and andesite. Bedrock is granite with amphibolite to the west and slate, schist, and serpentine to the east. There are also a few gold-quartz veins in the district.
Bibliography
Logan, C.A., 1929, Sierra County, Indian Hill mine: California Diy. Mines Rept. 25, pp. 192-193.
MacBoyle, Errol, 1920, Sierra County, Indian Hill mining district: California Min. Bur. Rept. 16, pp. 13-14.
Turner, H. W., 1897, Downieville folio: U.S. Geol. Survey Geol. Atlas of the U.S., folio 37, 8 pp.
