Here is a fossil that is not often seen in your everyday fossil collection. It is the iridescent shell of a Baculite. This is an extinct cephalopod that lived during the Cretaceous Period. They are related to the more popular ammonite. However, their shells were straight instead of coiled. The shell of aragonite and conchiolin creates thin layers with lots of color play due to interference of light.
You will receive the specimen pictured. Colors may vary based on screen size and resolution. The colors of the specimen will depend on the angle of display.