What a fabulous specimen the sutures are so distinct and as you can see from the scanned images it will make a real addition to any collection
Ammonite History and Uses:
Ammonites are invertebrates and extinct members of the subclass Ammonoidea, class Cephalopoda. Modern members include the nautilus, squid, cuttlefish and octopus. Ammonites first appeared during the Middle Devonian Period around 400 million years ago. They became especially abundant and widespread in the seas of the Jurassic and Cretaceous periods, 175 million to 65 million years ago. Ammonites were mollusks with shells that were predominantly tightly coiled on a single plane like a wheel. The shells of ammonites had hollow chambers separated by walls called septa. A tube called the siphuncle, connected the body with the chambers allowing the animal to fill them with water or air, changing its buoyancy in order to rise or descend in the ocean water column. The soft-bodied animal living in this shell most-likely resembled an octopus but with shorter arms. Only the last and largest chamber was occupied by the living animal. As it matured and grew, larger chambers were added at the opening. Ammonites varied in size from 2 meters (6.5 feet) down to 2 cm (0.75 inches) in diameter.