MOTHER-OF-PERAL

Specimens of the genus Douvilleiceras are probably among the most beautiful ammonites of all.

However, they only reveal their beauty when the shell with its bizarre knots and ribs is preserved, as is the case here.

The two specimens in the display cabinet on the left still have their original mother-of-pearl shell – in the two darker pieces on the right, the mother-of-pearl has been replaced by the mineral calite over millions of years. Both have their very own visual appeal.

The Cleoniceras in the left-hand display case also still has the iridescent mother-of-pearl on its surface – as does the small Desmoceras, which was probably washed into the entrance to the living chamber of the larger ammonite by a current on the sea floor.