IRIDESCENT AMMONITE

Placenticeras costatum
Late Cretaceous, Maastrichtian, circa 71 million years
Bearpaw Formation, Alberta, Canada
Mounted on a custom steel stand
63 × 56 cm (without stand)

Ammonite is an organic gemstone known for its exquisite iridescence and unique origins.
This nearly 32-centimetre-large example exhibits remarkably colourful iridescence, consisting of vivid patterns of red, orange, yellow, green and blue, and is in a grey shale matrix.

This is a truly exceptional ammonite specimen as demonstrated by the diversity of colours, intensity of iridescence, size, and quality of preservation.