A stunning example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 115 mm (4.5 inches) tall and the ammonite measures 90 mm across, which is large for this species. The shell sits in the limestone matrix in which it was found that has been shaped and has a cut-flat base and rock-coloured plaster wedge on the back to allow it to be displayed freely standing. The ammonite is very well preserved and has been prepared out of the rock to reveal the shell. The shell displays some beautiful iridescence with different copper and red tones appearing as the viewing angle changes.
These fossils are highly sought after and very hard to find. They are preserved in the same way as the famous Canadian "Ammolite" ammonites that are turned into valuable gemstones. The fossil weighs 230 grams.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.