1.55" Fossil Echinoid (Holectypus) - France
This is a fossil urchin of the species Holectypus sarthacence, from the Middle Callovian stage of the Middle Jurassic period (~165 Million Years Ago). It was found in Chaufour, France. The pressure of the surrounding rock led to the breakage of this urchin, however the shell is held stable by the naturally embedded rock within the urchin. It measures 1.55" in length.