A mineral shop owner in Calgary (Canada), Marcel Charbonneau in 1967 named ammolite, because it crystallized on the surface of ammonites. He made doublets (glued two layers of gems) of them, under ammolite, upper rock crystal. After these, this interesting gem has been known. Scientists noticed it in 1908, but it became a ’gemstone’ offically in 1981. Its other names are Korite (after Korite International mining company) and Calcentite. Ammolite is the fossil shell of ammonites transformed into laminated aragonite which is usually 0.5-0.8 mm thick. On this thin shell beautiful colors ’appear’, similar to precious opal due to the interference of light. Its classic locality is Alberta in Canada on the east side of the Rocky Mountains. The best quality is mined there, the ammolites with the thickest layers and the most various colors. Other localities: USA (Montana, Utah), Morocco, Madagascar, England.