A stunning example of an iridescent ammonite fossil of the species Psiloceras planorbis from North Somerset, UK.
The piece of limestone matrix measures 168 mm (6.6 inches) across and contains two ammonites, the largest of which measures 56 mm (2.2 inches), which is a good size for this species. The ammonites are well preserved and have been prepared out of the rock to reveal the shells, which display some beautiful iridescent colours that change depending on the angle that the fossil is viewed at with a copper sheen. The fossil weighs 580 grams and has a cut-flat base to allow it to stand freely on its own for display.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection. These fossils are preserved in the same way as the more famous Canadian "ammolite", which is turned into valuable gemstones due to the stunning iridescence.