Exquisite Split Cleoniceras Cretaceous Ammonite

This spectacular ammonite is a Cleoniceras besairei from Madagascar which has been split in half and polished to show the wonderful detail within. Some of the individual chambers are open and filled with rich cream colored calcite crystals, with the septa (divisions) between each chamber preserved as calcite, making for a superb display piece. Portions of the exterior shell is preserved as mother of pearl, an opal-like and iridescent mineral sometimes called ammolite; the color you see often changes as the angle of viewing or of light source changes, because of multiple reflections within layers of the material. Other portions exhibit the intricate suture patterns of the animal.

This is a top grade specimen - lessor grade specimens often have chambers infilled with matrix material, e.g., see the bottom center image for an example of what to look for.