Ammonoidea were nautiloid cephalopods that floated through the world's oceans for over 350 million years in the lead-up to the catalysmic extinction at the end of the Cretaceous period.
Named after the Egyptian god Amun - often depicted with Ram's horns - the fossils have a ripping spiral shell, protecting the animal's soft insides. The shell is filled with numerous chambers (visible in bisections); it is thought that by controlling the amount of water in each of these chambers the creature was able to control its buoyancy, and hence float through the water.
As they existed on planet earth for such a long period of time, there are many different species of ammonites, and they are often used as a reference to date other fossils found in the same sedimentary layer. Iconic in their shape, these fossils have been known and collected since ancient times.
- Sustainably sourced in Europe.
- Approximate Dimensions: 6cm across
- Approximate Weights: 0.05