A stunning example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 130 mm (5.1 inches) across and contains a single partial ammonite, which measures 42 mm. The shell sits in the original limestone matrix in which it was found. The ammonite is very well preserved and has been prepared out of the rock to reveal the shell, which displays some truly stunning multi-coloured iridescence with bright green and blue dominating. Green and blue are the most sought after, and hardest to find, colours in these fossils. The matrix has a cut-flat base to allow it to stand freely for display either on its side or as a tall display piece.
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 255 grams.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.