11.2" Cut & Polished Perisphinctes Ammonite - Madagascar

Cut & Polished Perisphinctes Ammonite - Madagascar #31818

This is a stunning, 11.2" wide cut and polished, Perisphinctes sp. ammonite collected near Sakaraha, Madagascar. Most of the cut and polished ammonites that you see from Madagascar are Cretaceous in age, so these large Jurassic ones are much more unusual.

The previously hollow chambers of the ammonite were replaced with a beautiful agate during the fossilization process. Some of these chambers are still partially hollow and lines with druzy crystals. The ammonite was cut in half and polished revealing the inner chamber structure of this ancient, marine animal. Both halves are included and they come with a pair of display stands.

As with most large ammonites there is some repair work and restoration to the outer surface (non display) side of the ammonite.

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.

What an ammonite would have looked like while alive.

More about ammonites