This Specimen has been sold.
2.8" Ammonite (Promicroceras) Fossil Cluster - "Marston Magna Marble"
This is a piece of rock containing many small ammonite fossils, often referred to as "Marston Magna Marble". The ammonites are of the species Promicroceras marstonense and are Lower Jurassic (~200 million years old) in age. This rock is quarried from near Marston Magna, Somerset, England. The base has been cut flat so it will display without the use of a 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.