Orthoceras Mortar and PestleAmmonites first appeared about 240 million years ago, though they descended from straight shelled cephalopods called bacrites that date back to the Devonian, about 415 million years ago. Ammonites were prolific breeders, lived in schools, and are among the most abundant fossils found today. Ammonites are very powerful earth fossils. Its spiral shape symbolises continual change and evolution. They have absorbed cosmic energy over eons of time and help