A stunning example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 98 mm (3.82 inches) tall and contains a large ammonite that measures 80 mm (a good size for this species in this condition). The ammonite shell sits in the original limestone matrix in which it was found and is very well preserved. The shell displays some beautiful multi-coloured iridescence with different colours appearing as the viewing angle changes. The matrix has a cut-flat base to allow it to stand freely for display.
These fossils are highly sought after and very hard to find, especially complete like this. They are preserved in the same way as the famous Canadian "Ammolite" ammonites that are turned into valuable gemstones. The fossil weighs 145 grams.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.