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Alexandrite : Color Change
Magic
One of the most fascinating gemstones
throughout history is alexandrite: a gem variety of the mineral chrysoberyl that
actually changes color from green in daylight to red in incandescent light. The
first time you see it, it is hard to believe your eyes! Gems that show special
optical effects are known as phenomenal stones. Chrysoberyl dominates this
category, because not only is alexandrite the most spectacular color change gem,
cat's-eye chrysoberyl has the most dramatic eye. Alexandrite has a distinguished
and glamorous past: it was discovered in 1830 in Czarist Russia. Since the old
Russian imperial colors are red and green it was named after Czar Alexander II
on the occasion of his coming of age.
Alexandrite can be found in jewels of
the period as it was well loved by the Russian master jewelers. Master
gemologist George Kunz of Tiffany was a fan of alexandrite and the company
produced many rings featuring fine alexandrite in the late nineteenth and early
twentieth century, including some set in platinum from the twenties. Some
Victorian jewelry from England features sets of small alexandrites.
Alexandrite is also sometimes available
as an unset stone but it is extremely rare in fine qualities. The original
source in Russia's Ural Mountains has long since closed after producing for only
a few decades and only a few stones can be found on the market today. Material
with a certificate of Russian origin is still particularly valued by the trade.
Some alexandrite is found in Sri Lanka and Zimbabwe and Brazil but very little
shows a dramatic color change. For many years, alexandrite was almost impossible
to find because there was so little available.
Then in 1987, a new find of alexandrite
was made in Brazil at a locality called Hematita. The Hematita alexandrite shows
a striking and attractive color change from raspberry red to bluish green.
Although alexandrite remains extremely rare and expensive, the production of a
limited amount of new material means a new generation of jewelers and collectors
have been exposed to this beautiful gemstone, creating an upsurge in popularity
and demand.
When evaluating alexandrite, pay the
most attention to the color change: the more dramatic and complete the shift
from red to green, without the bleeding through of brown from one color to the
next, the more rare and valuable the stone. The other important value factors
are the attractiveness of the two colors - the more intense the better - the
clarity, and the cutting quality. Because of the rarity of this gemstone, large
sizes command very high premiums.
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