Here is a an extension of the same fossil horizon known to paleobotanists as "Lygodium Gulch" (named after the common to abundant remains of a fossil climbing fern, whose closest modern analog is Lygodium palmatum, the sole species of climbing fern native to North America--it's been found in Alabama, Mississippi and Georgia north to New England). It lies amidst a patch of the rare and protected Ione manzanita (the dark green, low-lying shrub) marked by the green arrow. I discovered this specific site during a visit to the Ione Basin in 1992. It is a rich horizon, bearing plentiful, exquisite leaves stained a striking reddish-brown (due to the mineral iron oxide) on a brilliant white matrix of feldspar-rich shale. The site has not been extensively quarried, collected from, but awaits future paleobotanical analysis.
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.