Gastrolith

Gastroliths are small stones swallowed unmistakenly by dinos. The stones were used for the same reason as the grits swallowed by birds. Gastroliths (gizzard stones) are a rare find. They are very round and smooth. they get this way becouse the stomach of the dino acts very much like a rock tumbler. Theise can be found in the rib cages of dinos or in coprolite (dino dung).