Screenshot of USGS Map
Chrysoprase and Moss Opal deposits, River Pines, Fiddletown Mining District, Amador County, California, USA
Wagner, D.L., Jennings, C.W., Bedrossian, T.L., and Bortugno, E.J., 1981, Geologic map of the Sacramento quadrangle, California, 1:250,000, California Division of Mines and Geology, Regional Geologic Map RGM-1A, 1:250,000.
The map is not exactly accurate for this location as there is significant overlap of rock types and the meta-volcanics ...