An exposure of the Middle Eocene Ione Formation, Ione Basin, in the vicinity of the Discovery Site--so-named because that's where I first found fossil plants in the Ione Basin on July 21, 1991. The foot-long geology rock hammer gives perspective to a nice outcropping of conglomerate in the Ione Formation. Local gravel beds such as these in the Ione Basin resemble the world-famous auriferous, gold-bearing gravels that occur higher up the western slopes of the Sierra Nevada, in the neighborhood of Grass Valley/Nevada City, where hydraulic miners of the mid to late 1800s laid bare mile after mile of California's northern Mother Lode country to extract the precious metal from Eocene strata that most geologists (though not all, mind you) believe correlate at least in part with the Ione Formation exposed in the Ione Basin. Image taken on March 11, 2004.
Please note: All fossil localities in the Ione Formation of Amador County, California, presently occur on private property; explicit permission from the land owners must be secured before collecting fossils there.