Ammolite
CaC03

What color is it?: As you can see above ammolite is a beautiful rainbow of colors from intense blue/greens to very fine orange/reds. At left you see what is considered the finest color of ammolite, the beautiful intense red color. Although most ammolites will offer a variety of spectral colors as they are rotated in the light, those with dominant red colors are considered the most prized and most valuable.

What is the story behind this gemstone?: This is an organic stone that, in spite of its name and origin, is not a true fossil gem material like amber. Instead, the shell from the ancient ammonite has been compressed to the point that the calcium carbonate has been recrystallized to form a new material called aragonite. For most of you this will not be important, but for gemologists you will want to take note of this fact later on. For consumers, think of it as nature taking something old and beautiful, and making it into something new and beautiful that only occurs in one place and in one method.

Can I wear it everyday?: Yes, if the gem is set in a triplet mounting. These gems are very fragile in their native state as shown by the photograph at left being sold on eBay, so they must be set between a layer of what is generally black onyx on bottom and clear quartz on top. With these protective materials set with the gem ammolite you can wear it almost anywhere with the usual care and caution for any rare gem material.

Is it expensive?: Generally yes. The finer qualities will be quite expensive. This is a very, very rare and unusual gem material. So be prepared to pay dearly for a nice color piece of good size. The ammolite in the photograph at left measures approx. 1 inch long and costs approx. US$200.00 on the retail market. Larger pieces will be even higher on a per item basis.

Is it a birthstone?: No.

What do I need to know before going shopping?: Do not expect to find this gemstone is just any jewelry store. You will need to find a store who deals in exotic gemstones, and/or one who has a qualified gemologist on staff who can make sure you are getting the real thing. It may take a while for your local jeweler to find you some nice stones to choose from. But be patient. This is something that no one else on your street will own so make sure you get a good one.

General Information

Raw fossilized ammonite straight from the ground showing orient of ammolite in shell. Note the very thin shell layer.

Source: The finest are from Alberta, Canada
Chemical: CaCO2 (calcium carbonate)
Formation: Found in rare strata of fossilized ammonite beds in ancient sea floors which have been uplifted to the Canadian highlands.
Crystal System: None
Unusual Properties: Very fine orient or pearlessence.
Treatments: Examples of fake ammolite are starting to show up on the market. As seen below, this is an ammolite with a large created red area that can be identified by the fact that the colors do not alter when rotated under the light. Since red is the most valuable color someone used a red dye in the top clear coating material of this stone to make it appear to have a dominant red color.

a publication of the International School of Gemology 24 July 2015