Very large fossil ammonite (110 million years). This Procheloniceras sp. lived in the Cretaceous, more precisely in the Aptian. This specimen comes from the region of Erfoud, on the border between Morocco and Algeria. It was cleared of a rather hard matrix, and the center is very exceptionally clear. This specimen was then reworked with a stone chisel to highlight the ribs of this giant shell. This dimension is rare among ammonites and we discover a limited number each year.