Alexandrite is a rare gemstone that was reportedly named in honor of the future tsar Alexander II of Russia. Its most prized feature is that it changes color under different lightsources.
High quality alexandrite is exceedingly rare and quality natural alexandrite jewelry is hard to find in most gemstone shops today.
What is Alexandrite?
Alexandrite was discovered in the early 1830s in the emerald mines near Tokovaya in the Ural Mountains, Russia. The alexandrite is a gem-quality chrysoberyl.
Which is not the same as beryl, another type of mineral that includes emerald, aquamarine and morganite. Alexandrite is is best known for its color change called the alexandrite effect. Though green by daylight it changes to a red or purplish-red color by incandescent light.
This very rare gemstone can only be formed under very specific circumstances. Which unfortunately have rarely occurred in the history of the earth. Beryllium (a large part of the chrysoberyl mineral) and chromium (the element that is responsible for the alexandrite color change) are two elements do usually do not exist together. Not only that, but when these elements are present in the same area emeralds are almost always formed instead.
Most of today’s alexandrite is still from Russia. Though the deposits there have almost been depleted. In 1987 the first alexandrite outside of Russia was found in Brazil. Several other deposits were found since then in Tanzania, Sri Lanka and several other countries. Most notable is the find in Tanzania where some beautiful alexandrite gemstones have been unearthed. Still none of these new deposits are producing gems that are as beautiful as the Russian alexandrite.
Synthetic alexandrite is usually marketed under the name lab created alexandrite or czochralski alexandrite. It quickly made its way to the market since being developed in 1964. Czochralski or pulled alexandrite is relatively easy to identify because of its clarity. Another way to identify it is that when magnified the crystals show striation (stretchmarks).
Flux grown alexandrite however is far more difficult to identify. Mainly because the process leaves inclusions in the gemstone that appear natural. This process is the reason that you should always ask for certification. While only dealing with gemstone shops that have a high reputation. Even experts have trouble identifying a flux grown alexandrite without proper equipment. So there is no shame in requiring assistance when purchasing an alexandrite.
Alexandrite prices are so high that even synthetic alexandrite is faked. A lot of gemstones that are claimed to be synthetic alexandrite are actually synthetic corundum with added vanadium. The easiest way to recognize this material is that even though it possesses the prized alexandrite color change. There never is any green under natural light. Some of these stones can be considered antique as the first of these stones came on the market in the early 1900s! Age is no guarantee for a natural stone in this case.
Alexandrite Buying Guide
The color change is the most important factor in determining alexandrite value. Clear green to clear red or purple is highly sought after. Clarity is the second factor, most natural alexandrite gemstones will have some inclusions unless dealing with the most expensive stones.
Another thing to keep in mind is windowing. A gemstone is windowed when part of the gem does not disperse the light back to the viewer. Meaning that a part of the gemstone will look dull. Gemstones without windows will fetch a price that will be 30-50% higher! The reason for this is the fact that a one carat gemstone with windowing usually becomes a 0.65-0.75 carat gemstone without windowing.
Russian alexandrite is considered the most beautiful of all alexandrite. So their prices will be higher if it can be proven that it was found in Russia. Only pay this premium when it is proven beyond doubt that this is the case. Most mines in Russia that produced alexandrite are exhausted today so keep that in mind when a Russian origin is claimed.
Be absolutely sure about whether you are dealing with a natural stone, a synthetic stone or even a fake synthetic stone. When you want a high quality stone for a good price, you should go for a lab created alexandrite. There is no need to settle for a fake synthetic alexandrite. Lab created gemstones come in all sized and shapes and can be bought for very reasonable prices.
When you are looking for a natural stone the price will increase sharply. Several thousand dollars/carat to over $10,000/carat for a high quality stone is no exception. So please only deal with shops that have a high reputation. Proper certification and a good return policy is also very important.
If you can get your hands on a alexandrite it will be one of the most beautiful gemstones you have ever seen. The color change is breath-taking, but unfortunately so are the prices.