A stunning and perfect example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 232 mm (9.15 inches) across and contains an ammonite that measures 90 mm (3.6 inches), which is large for this species. There are also some tiny juvenile ammonites preserved next to the main shell.
The shell sits in the original limestone matrix in which it was found that has been shaped and has a cut-flat base and plaster wedge on the back to allow it to be displayed freely standing. The partial ammonite is very well preserved and has been prepared out of the rock to reveal the shell, which displays some beautiful iridescence with the colours changing as the viewing angle changes with red and copper colours present.
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 550 grams.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.