Minerals are naturally occurring ... Crinoids first appeared in Early Ordovician rocks. Although crinoids still exist today, the species found in Cincinnatian rocks disappeared at the end of the ...
How could a modern artifact be stuck in Ordovician rock? The answer is that the concretion itself is not Ordovician. Minerals ...
Saturday, Nov. 2, at 10 a.m. at Lowe-Volk Park, 2401 State Route 598.