A close up of the top of a sea shell shows the intricate layering of the way the off white shell was formed. The layers of the shell almost appear star like and each layer rotates slightly more that the previous layer, each layer becoming smaller than the layer before it.
ammonite: Per Wikipedia the ammonites went extinct with Dinosaurs 65 million years ago. Ammonites survived until the end of the Cretaceous period in a sea that covered what is now Alberta. Canada and Montana, USA. These ammonites were transformed into the rare gem known as Ammolite.