One of the easier fossils to prep with sand abrasion cleaning are specimens from the Silver Creek Member, North Vernon Limestone of Clark County, Indiana USA. I believe it is this layer of limestone that the county's large concrete plant uses to manufacture product. This fossil is the Orthospirifer brachiopod and it has a nice colony of Aulopora coral growing on it. The brachiopod and coral lived in the Middle Devonian Period.
Thanks to Kenny for cleaning this one up for me!
