Add this item to your order to let your Account Manager know you are interested in learning more about the current availability of ammolite. Pricing varies greatly based on size and quality.Ammolite is a rare opal-like organic gemstone found along the eastern slopes of the Rocky Mountains in Alberta. It is made of the fossilized shells of ammonites, which are composed primarily of aragonite, the same mineral contained in Mother of Pearl. The ammonites inhabited a prehistoric, inland subtropical sea and is known today as the Western Interior Seaway. The iridescent colour of ammolite comes from interference with light from stacked layers of thin platelets of aragonite. The thicker the layers, the more reds and greens produced.