The rare gemstone alexandrite is named after the Russian tsar Alexander. The first crystals were discovered in 1834 in the emerald mines of the Ural Mountains, at the same time as the new tsar came of age.
Showing nuances of red and green, the principal colors of Imperial Russia, alexandrite inevitably became the national stone of tsarist Russia. Russia remained primary source of alexandrite since gems from the Ural Mountains became available on the market. Alexandrite from mines elsewhere hardly displayed the coveted color change, but the situation changed in 1987 with the discovery of new mines in Brazil where alexandrite has shown similar characteristics to the high quality mined in Russia.
Due to its scarcity, alexandrite is seldom found in modern jewelry. It was used by Russian master jewelers in the 19th century and the Victorian gemologist George Frederick Kunz showed his fascination for the gemstone by having his firm produce a series of rings and ensembles using alexandrite.
The scarcity of this gemstone is due to its chemical composition. Basically a chrysoberyl, it differs from other varieties of this transparent mineral by containing not only iron and titanium, but also chromium as a major impurity and the coloring factor in alexandrite.
The most sensational feature of this gemstone is its ability to change color. Green or bluish-green in daylight, alexandrite turns a soft shade of purplish-red or raspberry red in incandescent light. This unique optical characteristic has made alexandrite a most valuable gemstone and determines its price depending on the degree of ability to change color.