Location
This is a small gold-mining district in central San Diego County about 50 miles east-north-east of San Diego and five miles west of Cuyamaca. Gold was discovered here about 1885, and minor work continued intermittently until the 1930s.
Geology
The district is underlain by granitic rocks and mica schist. A number of narrow north-striking quartz veins in shear zones contain free gold and varying amounts of sulfides, including pyrite, pyrrhotite, arsenopyrite, and marcasite. Some silver is present, and tellurides have been reported.
Mines
Boulder Creek, Elk, Gold Crown, Last Chance, Lucky Strike, Nona, Penny, Prosperity.
Bibliography
Everhart, D.L., 1951, Boulder Creek district: California Div. Mines Bull. 159, pp. 109-111.
Tucker, W. B., 1925, San Diego County, gold: California Min. Bur. Rept. 21, pp. 331-349.
Weber, F. Harold, Jr., 1963, San Diego County, gold: California Div. Mines and Geology County Rept. 3, pp. 115-167.