Photo of Alexandrite in Processed & Rough Form
Alexandrite is a mineral with a hardness of 8 out of 10 on the Mohs scale of mineral hardness [?]. These Orthorhombicly structured gems are made of beryllium aluminum oxide, their full chemical compound being BeAl2O4.
Alexandrite is one of the more rare varieties of color changing chrysoberyl that changes color depending on the type of light that hits it. In daylight it generally appears greenish, while it appears red while indoors due to the incandescent lighting.
This gem was first discovered in the Ural Mountains of Russia in the 1830s, but has since been found in Sri Lanka, Brazil, and even East Africa. This gem is extremely rare and is generally very expensive especially as a cut gemstone.
Combine its color changing properties, with its hardness scale of 8.5, and you can see why this stone is so highly coveted by those in the know.
What makes Russian Alexandrite so valuable?
Original Russian alexandrite from the Ural Mountains shows the most dramatic color change from emerald green to raspberry red. These historically significant stones set quality standards. Fine specimens over one carat can exceed the per-carat price of diamonds.
How can I tell natural Alexandrite from synthetic?
Natural alexandrite typically shows internal features like needles or fingerprints, while synthetics often have curved growth lines and gas bubbles. Natural stones rarely show perfect color change, and inclusions appear more random than in synthetics.
Why do some Alexandrites appear more purple than red?
Color change quality varies with composition. The finest stones show pure green to red change. Lesser stones may shift from bluish-green to purplish-red. Brazilian stones often show more brownish tones than Russian material.
Are Cat's Eye Alexandrites real?
Natural cat's eye alexandrite exists and is extremely rare. These specimens show both chatoyancy and color change, making them among the most valuable phenomenal gems. Most originate from Sri Lanka or Brazil.
Why such extreme price variations?
Fine natural alexandrite is one of the rarest gems. Prices reflect dramatic differences in color change quality, origin, and size. Even small differences in quality can create huge price jumps, especially above one carat.
Are Brazilian Alexandrites inferior to Russian?
While Russian material remains the benchmark, Brazilian alexandrites can show excellent color change. They tend to have different color combinations but can be equally valuable if they show strong, attractive color shifts.
What lighting shows true Alexandrite color change?
Optimal color change is seen between natural daylight and incandescent light. LED lights may produce different effects. Professional dealers use specific daylight and incandescent bulbs for consistent evaluation.
The specific gravity [?] for Alexandrite is 3.71, its refractive index [?] is 1.74-1.75, and its double refraction [?] is 0.009.
History
Being first found it Russia, Alexandrite was named after Tsar Alexander II, and legend has it this gem was found on his coming of age day.
Industrial Usages
Due to its rarity this gem or stone is too valuable to have any legitimate uses in the industrial world.
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