A stunning example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 95 mm (3.75 inches) tall and contains two partial ammonites. The shells sit in the original limestone matrix in which they were found. The ammonites are very well preserved and have been prepared out of the rock to reveal the shell details. The shells displays some beautiful multi-coloured iridescence with most of the colours of the rainbow that appear as the viewing angle changes, with rare green and blue tones in parts. Green and blue are the rarest colours on these fossils and the most sought after. 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 250 grams.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.