This Specimen has been sold.
5.9 Inch Wide Halved Ammonite From Madagascar
Here is half of a 5.9 inch wide ammonite fossil from the Cretaceous of Madagascar which has been cut and polished. It shows the amazing inner detail with some of the chambers replaced by pockets of crystals. The reverse side has a "mother of pearl" colored shell with some of the "oak leaf" shaped sutures visible. Simple gorgeous.
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. Ammonites appeared in the fossil record about 240 million years ago and they barely survived several major extinction events. The last lineages disappeared 65 million years ago at the end of the Cretaceous.