Small amounts of placer gold have been recovered in some of the canyons in the Santa Ana Mountains in southeastern Orange County. The most productive have been Trabuco, Silverado, and Santiago Canyons. The town of Silverado flourished until around 1881. Prospecting was first done here many years ago, and there was some activity again during the 1930s. A number of narrow veins in the region contain varying amounts of tin, copper, zinc, and small amounts of gold.
Larson, E. 5., 1951, Crystalline rocks of southwestern California metals: California Div. Mines Bull. 159, pp. 46-49.