Relatively new to the gemstone world, ammolite was recognized by the Colored Stones Commission in 1981 as one of only three organic gemstones; the other two being amber and pearl. The calcium carbonate that composed an ammonites shell, is the same material that forms the nacre of a pearl. During geological processes, this material transformed into a type of aragonite, resembling a mica-like substance, with many, many layers on the matrix, which is usually a dark brown or gray to black jasper-like or slate material. As such, ammolite is very soft, registering only about a 3.5 to 4 on Mohs scale, and to be used as a lapidary material it needs to be stabilized. One type of stabilization is to force epoxy into the many layers, fusing them together. Another way is to make the featured specimen into either a doublet or a triplet, and sometimes a whole ammolite fossil is simple protected by a simple layer of acrylic coating to protect the specimen for display purposes. All ammolite on the market for jewelry-making has been stabilized.
A wonderful display of ammolite cabochons and specimens for sale at the Tucson gem shows in 2009.