Coprolites are known to be the fossilized excreta of a variety of organisms that differ greatly in size and habitat and include microscopic aquatic animals, fish, turtles, mammals, and reptiles.

They have been found in many parts of the world in beds of marine and fresh-water shale and limestone, in volcanic ash, and in cave deposits.

Coprolites consist principally of tricalcium phosphate and some contain extraordinarily well-preserved remnants of partially digested foods; such as, muscle fibers and the tissues and seeds of identifiable plants.