Found this by Southfield Road, Lathrup Village, Michigan more than 50 years ago, so it could have come in limestone used for road construction. Is it a fish fin (as I assumed at the time) or perhaps a crinoid crown?
Found this in the bottom of a creek bed in Cleburne Texas. I think it's bone. Maybe a fin or a tiny rib cage. Anybody have any ideas? I forgot to put a comparison next to it but the fossil is quarter size. The entire piece is about 2 quarters in length.