The Kelsey district is in northwestern El Dorado County. It is that portion of the Mother Lode gold belt that extends from the vicinity of the town of Kelsey northwest to Garden Valley.
This area was placer-mined soon after James Marshall's gold discovery in 1848 at Coloma, a few miles to the west. The camp was first settled by and named for Benjamin Kelsey. Marshall spent his last days at Kelsey, and a building on his property once housed a pioneer museum. There was much lode mining from the 1860s through the early 1900s and again in the 1930s. Some intermittent work has been done recently at the Black Oak mine.
Geology and Ore Deposits
A northwest-trending two-mile-wide belt of gray to black slate of the Mariposa Formation (Upper Jurassic) is in the central portion of the district, with greenstone, slate, graphite schist, and quartzite to the west. Amphibolite, slate, and schist lie to the east. Serpentine lenses are also present both to the east and west. The ore deposits occur in quartz veins with numerous stringers. The veins range from one to 10 feet in thickness. Nearly half of the known output of some of the mines has been from small but extremely rich ore shoots. None of the mines has been worked to depths of more than 600 feet.
Big Four, Big Sandy $100,000+, Black Oak $1.25 million, Gopher Hill, Gray Eagle, Hart, Ida Livingston, Kelsey $100,000+, Lady Emma, St. Clair, Veerkamp, War Eagle, Yuba.
Clark, W. B., and Carlson, D. W., 1956, EI Dorado County, lode gold deposits: California Jour. Mines and Geol., vol. 52, pp. 401-429.
Fairbanks, H. W., 1890, Geology of the Mother Lode region: CaliÂ¬fornia Min. Bur. Rept. 10, p. 81.
Lindgren, Waldemar, and Turner, H. W., 1894, Placerville folio, California: U.S. Geol. Survey Geol. Atlas of the U.S., folio 3, 3 pp.
Logon, C.A., 1935, Mother Lode gold belt of California-Big Sandy, Black Oak, and Kelsey mines: California Div. Mines Bull. 108, pp. 19-21 and 29.