These primitive cephalopods are approximately 400 million years old. Orthoceras are related to the modern squid or octopus. They are similar to ammonites, but have a straight shell rather than a coiled shell. These fossils exist as white fossils in a dark gray or black marble matrix.
The listing is for one small ammonite from Morocco. It is polished on the front and rough on the back. It is approximately 1.5 inches long. It may contain minor craters or scratches.