Location and History
This district is in the east-central Placer and Nevada Counties in the vicinity of the towns of Emigrant Gap and Blue Canyon. It is both a lode and placer gold-mining district that was first worked during the gold rush. There has been intermittent prospecting and development work here since. The Zeibright mine was worked on a large scale during the 1930s. The Washington district is just to the northwest and the Westville district is to the south. The Zeibright mine camp is now a boy scout camp.
The district is chiefly underlain by thick beds of slate, schist and phyllite of the Blue Canyon Formation (Carboniferous). To the north and west these rocks are overlain by andesite and rhyolite tuff. There are several patches of auriferous Tertiary channel gravels.
There are a number of north-trending quartz veins in schist and slate that contain free gold, pyrite, and small amounts of other sulfides. The veins range from one to 10 feet in thickness and consist of a series of parallel quartz stringers. The milling-grade ore usually contained 1/2, ounce per ton or less, but some of the ore shoots were extensive. Channel deposits at the Lost Camp hydraulic mine contain both cemented and free-washing quartzitic gravels. These gravels are overlain by sands and volcanic rocks. Some of the gold recovered from the gravels was coarse.
Lode: Red Rock, Texas, Van Avery, Zeibright $1 million+. Placer: Golden Channel, Golden Nugget, Lost Camp, Shell, Wild Yankee.
Lindgren, Waldemar, 1900, Colfax folio. California: U. S. Geol. Survey Geol. Atlos of the U. S., folio 66, 10 pp.
Lindgren, Waldemar. 1911, The Tertiary gravels of the Sierra Nevada: U. S. Geol. Prof. Paper 73, p. 146.
Logan, C.A., 1936, Gold mines of Placer County, Lost Camp Mine: California Division of Mines Rept. 32, p. 68.
Logan, C.A., 1941, Nevada County, Zeibright Mine: California Division of Mines Rept. 37, p. 431.
Waring, C. A., 1919, Placer County, Lost Camp Mine: California Mining Bureau Rept. 15, pp. 376-377.