A highly pyritised ammonite fossil of the species Polymorphites polymorphus from the world-famous Jurassic Coast beach of Charmouth, Dorset UK.
The fossil measures 20 mm (0.8 inches) across. The ammonite is very well preserved on both sides. The ribs are very finely defined and the pyritic colour and shine is beautiful. A great example of an uncommon species and incredible in the flesh.
These pyrite ammonites have long been used to make beautiful natural jewellery.
Around 196 million years old, this fossil would make a wonderful addition to any collection.