Catacoeloceras raquinianum (D'Orbigny 1844)

4cm. Pyrite Steinkern with a bit of shell left on it. This is the phragmocon. Most of the living chamber is missing, but one can see the calcite at the top which filled it. Found in a concretion on the beach at Ravenscar, Yorkshire, GB. Bifrons zone, lower Toarcian.