A stunning example of an iridescent calcite multi-ammonite fossil of the species Psiloceras planorbis from North Somerset, UK.
The piece of limestone matrix measures 131 mm (5.2 inches) wide and contains multiple fossil ammonites, the largest of which measures 75 mm, which is very large for this species. The ammonites are well preserved and have been prepared out of the rock to reveal the whole shells, which display some subtle iridescent colours that change depending on the angle that the fossil is viewed at and a nice silvery sheen. The largest ammonite has some very unusual distortion in the shape of the shell that appears to have been caused by geological movements over millions of years. The fossil weighs 275 grams and has a cut-flat base to allow it to stand freely for display.
Around 200 million years old (Hettangian, Early Jurassic), this fossil would make a wonderful addition to any collection.