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| Formula: | BeAl2O4 |  Click to see a larger image |
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| Crystal: | Orthorhombic | |||
| Hardness: | 8.5 | |||
| Spec. Gr.: | 3.75 | |||
| Streak: | Uncolored | |||
| Cleavage: | i(001) quite distinct | |||
| Location: | Malysheva, Ural Mountains, Russia |
| Alexandrite is a very unusual gemstone. In daylight it appears to be a rich green color, but under artificial light it becomes red. It was first found at Tokovaya, Russia on April 23, 1830 the exact day that young Czarevitch Alexander Nicolajevitch came of age. It was named Alexandrite for the royal youth who would become Czar in 1855. It became immensely popular when in addition to its timing with Nicolajevitch; its colors of red and green were Russia's national military colors. The stone is looked upon as a good omen in Russia. Alexandrite occurred in jumbo-sized pseudohexagonal crystals up to 8 cm in diameter. The 6.4 cm alexandrite in the UCSB Geology collection is probably one in ten of existing single crystals which are of similar quality. The main reason that even ten crystals still exist is that large crystals tend to be heavily flawed and do not provide gem quality sections that could be worth a fortune. |
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Bibliography: Kunz, George Frederick, The Curious Lore of Precious Stones. Bancroft, Peter, Gem and Crystal Treasures. 1984. Pg. 463-467. |
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