1. Summary geochemical map for samples of rock, stream sediment, and nonmagnetic heavy-mineral concentrate, Freel and Dardanelles Roadless Areas, Alpine and El Dorado Counties, California [cartographic material] Yale Public content 1985. 2002-06-01T04:00:00Z. 2016-04-11T17:22:41Z. Geological Survey (U.S.). The Survey ; For sale by Branch of Distribution. English. Public. California, Alpine County, and El Dorado County.