Alexandrites
| SOURCES: Russia has long been the most desirable source for gem Alexandrite. The finest comes from the Takowaja emerald mines in the Ural mountains. This is where it was discovered in 1830. Alexandrite from Brazil is mined in the States of Minas Gerais and Bahia. Until the discovery of its new alexandrite vein, Brazil commanded little or no respect as an alexandrite producer. |
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.At present all major Brazilian mines are under government control. Recent finds have led to a great deal of infighting between mine owners. The "wars" became so violent that the government trenched a moat around and posted soldiers upon, the only remaining operating mine. For prized stones, the trade counts on Sri Lanka, but only on a sporadic basis. These stones always seem to have an undertone of brown or yellow. Seldom do you see the fine 100% color change exhibited in the new Brazil or old Russian material. Sri Lankan material can often exceed 20 cts. in size and be extremely clean. But the faint orange color change usually can only be seen in laboratory conditions.
NEW BRAZIL: Nobody knows how much material from the new Brazilian find has been cut. But insiders estimates range from 5,000 to 10,000 carats. These stones boast admirable color purity and richness. The completeness of the color change in most of the material is one of the most amazing things about the new find. As anyone who has seen new alexandrite knows, these stones challenge common experience with this species.
PRICE & SIZE: As of March 2000, fine quality 2-to-3 carat Brazilian stones were already commanding prices of $ 18,000 to $35,000 per carat. Although 30 to 40 carat Russian alexandrites are known to exist, most are around 8 carat and you rarely see Siberian stones that have the right color and purity. These stones can fetch upwards of $50,000 per carat. One should not forget that the primary buyers of alexandrite for some time now have been the Japanese. Especially fond of sizes between 2 and 4 carats, they have so far swallowed prices exceeding $15,000 per carat.
The nature of the alexandrite crystal and its unique trichoric phenomenon dictates the rough will be cut for purity, color change, and size. Stones are not cut to "calibrated" size, nor seldom is the rough wasted to cut stones over 4 mm round. Pearshape, emerald-cut, or navette likewise are not the shape of choice to which alexandrite is fashioned. Rather the antique or cushion shape, small rounds under 3 mm or elongated ovals dominate the finished supply.
Hardness: 8.5 Toughness: Excellent RI: 1.746-1.755 DR SG: 3.73 Group: Chrysoberyl Sources: USSR, Brazil, Sri Lanka Color: Daylight- bluish green Incandescent - Purple-Red Enhancements: None known