5.9 Inch Wide Halved Ammonite From Madagascar

Inch Wide Halved Ammonite From Madagascar #772

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 squids with shells. These cephalopods had eyes, tentacles, and spiral shells. Though their shells resemble that of a nautilus, they are actually more closely related to living octopuses. Ammonites appeared in the fossil record about 240 million years ago, barely surviving several major extinction events. The last lineages disappeared 65 million years ago at the end of the Cretaceous.

Artist's reconstruction of an ammonite, by Nobu Tamura

More about ammonites