These invertebrate creatures look somewhat like and are an ancestor of the octopus and the squid, except its body is covered by a coiled chambered shell.

Many had ornate ribs and markings on the outsides of their shells and range in size from a few millimetres to over two metres and form very appealing specimens.

Ammonites were carnivores, preying on small fish and free living invertebrates. The design of the Ammonite shells were divided into chambers, filled with water and air. The walls separating the chambers meeting the outside shell in beautiful wavy patterns, called sutures, which are an important means of identification. The animal lived in the largest chamber, just inside the opening, being attached to the centre of the shell by a thin cord in a tube, the sipho, protruding all the chambers.

Ammonites have been noted by mankind since Biblical times. First called Ammon's Stones because of their resemblance to the ram's horns of Ammon, the ancient Egyptian god of life and procreation, they have been collected and prized because of their aesthetic and geometrical beauty for thousands of years. It wasn't until the late 1700's that it was generally accepted that these "rocks" were the remains of once-living organisms.