A stunning example of an iridescent ammonite fossil of the species Caloceras johnstoni from North Somerset, UK.
The matrix measures 100 mm (3.96 inches) tall and contains a large partial ammonite shell that measures 64 mm across. The shell sits in the original limestone matrix in which it was found that has been shaped and has a cut-flat base to allow it to be displayed freely standing. The ammonite shell is very well preserved and has been prepared out of the rock to reveal the detail. The shell display some beautiful fiery iridescence that changes as the viewing angle changes, with blues, purples, greens, reds, oranges, and copper colours appearing. Having this range of colours in a single shell is rare, especially the blues and purples.
These fossils are highly sought after. They are preserved in the same way as the famous Canadian "Ammolite" ammonites that are turned into valuable gemstones. The fossil weighs 240 grams. These fossils make great unusual gifts and each one is totally unique.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.