The only gem on Earth made of a dinosaur-age animal: ammolite is the iridescent aragonite shell of Placenticeras ammonites that died in the Western Interior Seaway and were buried in the bentonite mud that became the Bearpaw Formation. The colour is structural, not pigment, and the best of it runs red and green like fire in the hand. The band reaches from Alberta into Saskatchewan and Montana, but the gem-grade material comes off the eastern slope in southern Alberta between Magrath and Lethbridge, and one operation, Korite, mines over 90 per cent of the world supply. It was given official gemstone status in 1981. Ammolite is fossil material, so Alberta’s fossil law applies to it: the mining is done under permit, and this is a place to understand rather than a place to dig.
Ammolite
Other places on the map within a couple of hours.
