Unique unpolished ammonite on golden pedestal.
Ammonites, like the nautilus, had a flat spiral shell. This shell was made up of different rooms. Every time the animal grew, a new larger outer room was added. The other empty chambers were used, among other things, as a means to keep moving vertically.
Ammonites are extinct and are a subspecies of cuttlefish. Ammonites were marine animals that occurred worldwide in large numbers.