This pyrite (pyritized) ammonite fossil is from the Lower Lias Deposits at Buttenhiem, Bavaria, Germany. This extinct ammonite was a cephalodpod similar to today’s nautilus. It is the species Pleuroceras which lived in the Jurassic Period about 185 million years ago. It has been prepared by cleaning, stabilizing and coating in a protective lacquer. It displays nicely from both sides. It measures 1 5/8 x 1 5/16 x 3/4 inches or 41 x 33 x 19 mm.