This extremely rare gemstone of fairly recent history owes its name to the fact that it was first discovered in the Urals in 1830, on the day of Prince Alexander of Russia’s coming of age.



Appearance:
Green: it can be almost emerald-colored, but is more often yellowish or brownish green. Its main characteristic is the ability to change color if exposed to a light source rich in red rays, by candle light of tungsten light, it turns red or reddish. This unusual phenomenon is what distinguishes it from other green chrysoberyl. This pronounced color change from green to red is highly priced and, as always, the exact tone of the colors, is important, the idle being the brilliant green turning to firry red, although dull green turning reddish or slightly turbid blood red is more common, and given alexandrine’s extreme rarity, even stones with a number of inclusions are cut. It is given an oval or round mixed cut or a rectangular, step cut. Alexandrite is so rare that few people have ever seen one; and perhaps for this reason, the name is applied to other, mainly synthetic stones not remotely like it (usually violet-colored synthetic corundum).



Distinctive features:
The changing color is unmistakable characteristic, however in the last few years, small quantities of green or bluish-color grosullar garnet that turn red like alexandrite have been found in East Africa. To distinguish between the two, it is useful to look for science of birefringence, as garnet, unlike alexandrite, is singly refractive. The refractive indices of the two stones, on the other hand, are very similar, as are their densities.



Occurrence:
Found in limited quantities in the soviet union, brazil, Sri Lanka, and some east African countries (Zimbabwe and Tanzania).



Value:
Fine stones are extremely valuable and on a par with emeralds, rubies, and sapphires. When the colors are dullish, the value falls applicably, but because of its rarity, are alexandrite is expensive, it is collectors’ item.


Simulants and Synthetics:
Attempts have been made in the past to imitate alexandrite change in color using synthetic spinal and corundum, but the result have been modest. More recently violet-colored synthetic corundum has been wisely marketed under the name of alexandrite, despite its lack of any real similarity to the natural stone. However, many who have never seen through alexandrite apply the name to this synthetic corundum and possibly for this reason, some manufactures of synthetic corundum’s call their violet stones “alexandrite.” Synthetic alexandrite has also been reproduced, but mainly for industrial purposes. For the time being, therefore, synthetic alexandrite is even rare than the natural variety.