Brilliant Agatized Sliced and Polished Ammonite (Pair)

Here is a beautiful and exotic 5.7 inch cut and polished Cleoniceras ammonite pair fromMadagascar. It exhibits gorgeous mineralization within the chambers with white calcite septa (divisions) separating them. This large, highly polished ammonite makes a great display piece with tremendous historical appeal.

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