This specimen is a fossil of a single ammonite shell, Pleuroceras, from Jurassic age rocks in Buttenheim, Germany.
Miniature Specimen: about 40mm x 35mm x 20mm (1.6" x 1.4" x 0.8").
The outer shell material has been replaced by pyrite, which has been polished to further enhance its appearance, contrasting with the matte grey calcareous matrix. This specimen exhibits beautiful detailing of the ridged whorls of the shell. Small irregularities in this surface represent suture patterns or other post-death alterations of the shell.