Ammonite (Aioloceras)

A Cretaceous age ammonite from Tulear, Madagascar. These ammonites are naturally iridescent. The one you receive will be of a similar size and quality to those pictured.

Ammonites were marine creatures that lived millions of years ago, during the Paleozoic and Mesozoic Eras. They were distant relatives of modern-day octopuses and squids, and their fossilized shells are often found in sedimentary rocks.  Ammonites had coiled shells that were often beautifully patterned. These shells were made of calcium carbonate, just like the shells of snails and clams. The shape and details of their shells can help scientists determine the age of the rock they are found in, making them valuable tools for geologists.

The iridescence in these Aioloceras besairiei ammonites comes from their preserved nacreous shell, a pearly layer made of aragonite (a type of calcium carbonate). This layer has tiny, stacked plates that are super thin—about the size of light waves. When light hits them, it bounces and splits, creating a rainbow effect as the light waves mix and shift with your viewing angle. Fossilization in Madagascar kept this structure intact, and polishing makes the shimmering colors pop even more.    

Each ammonite comes stored in a display box featuring the specimen name, region it was found, age and a QR code linking to some information about ammonites (the fossil can be removed from the box).

This is genuine fossil. All the specimens we offer come with a lifetime authenticity guarantee.

Condition: Good | Size: 1 - 1.25 inch | Age: 110 Million Years | Found: Tulear, Madagascar