The Mesa Grande gold-mining district is in north-central San Diego County just northeast of the town of Mesa Grande and about 50 miles northeast of San Diego. The deposits were discovered in late 1880s and were worked until about 1896. There was minor activity again in the 1930s. The principal source of gold has been the Shenandoah mine, which has yielded about $50,000. Others include the Black Eagle and Mesa Grande mines. The ore deposits consist of narrow northeast-striking gold-quartz veins in schist and gneiss. Some of the surface ore was rich.
Storms, W. H., 1893, Mesa Grande district: California Min. Bur. Rept. 11, p. 382.
Weber, F. Harold, Jr., 1963, San Diego County, gold: California Div. Mines and Geology County Rept. 3, pp. 115-167.