The fossil Gryphaeidae are older than the Middle Jurassic, their age is between 201.3 and 174.1 million years.
Hammer of Thor (fossil gryphaeidae).
Paradoxically it reminder also a sacred denier.
Typically white in attractive reflection given a pearly gloss.
Beautiful piece, valued by its shape and so special reflections.
The color changes with the lights of the environment.