Ammolite is formed from the fossilized shells of ancient sea creatures called ammonites. Seventy million years of tectonic pressure, heat, and mineralization resulted in the formation of an iridescent ammolite layer in the fossil. Although ammonite fossils can be found around the world, ammolite has only been found in one place, the Bearpaw geological formation in southern Alberta, Canada, making it one of the rarest gemstones.

The quality of ammolite is based on a combination of brilliance and diversity of color in the stone. The highest quality ammolite is very brilliant with every spectral color present. Particularly prized are ammonite fossils covered with ammolite. For hundreds of years, the Blackfoot tribe considered the gem a gift from the gods, possessing supernatural properties.

Natural ammolite is relatively soft, with a hardness of 3.5 to 4 on the Mohs Scale. However, many stones are capped with synthetic spinel, which provides protection. Since ammolite is a relatively delicate gemstone, it should be removed before strenuous activities. To clean, wipe with a soft damp cloth.