Example ammonite «Leioceras opalinum»

This extremely well preserved ammonite of the type «Leioceras opalinum» was found in the Opalinus Clay in the Benken borehole. It was protected and preserved by the clay from outside influences. The name of the fossil is derived from the opalescent sheen of the shell that has remained intact for around 180 million years. (Image: Comet).