This Specimen has been sold.
3.6" Jurassic Ammonite (Hildoceras) - England
This is a 3.6" Hildoceras lusitanicum ammonite from Whitby, England. These well preserved ammonites are Jurassic in age and are found in hard concretions that must be split open to reveal the fossil. The base of the rock has been cut flat, so that it stands up without the need for a display stand.
Ammonites were predatory mollusks that resembled a squid with a shell. These cephalopods had eyes, tentacles, and spiral shells. They are more closely related to a living octopus, though the shells resemble that of a nautilus. True ammonites appeared in the fossil record about 240 million years ago. The last lineages disappeared 65 million years ago at the end of the Cretaceous.