Alexandrite stands as one of June’s three recognized birthstones, distinguished as a remarkably rare and captivating gemstone. Its relatively recent addition to the birthstone canon – officially recognized in 1952 – belies a fascinating history intertwined with Russian royalty and a unique optical phenomenon. Described as “emerald by day, ruby by night,” this color-changing variety of the mineral chrysoberyl holds a special place in the world of gemstones, often commanding a value exceeding that of rubies and even diamonds. This article will delve into the history, geological origins, gemological properties, symbolism, and care of this extraordinary stone.
History and Lore
The story of alexandrite begins in the Ural Mountains of Russia in the 19th century. Discovered in emerald mines, the gemstone’s initial identification as an emerald was quickly overturned by Finnish mineralogist Nils Nordenskiöld. He observed the stone’s astonishing ability to shift color from green in daylight to red under the glow of a campfire. This remarkable characteristic led to its naming in honor of Czar Alexander II, whose coming-of-age coincided with the discovery in 1834.
The colors – red and green – held particular significance as they represented the colors of the Imperial Russian flag and the aristocracy, solidifying alexandrite’s status as the national stone of Tsarist Russia. The original Russian deposits established the benchmark for alexandrite quality, with stones from this region exhibiting the most vivid and dramatic color change.
Following the depletion of the Russian mines, alexandrite was subsequently found in Brazil, Burma, India, Madagascar, Rhodesia, Sri Lanka, Zambia, and Zimbabwe, though stones from these locations generally display a paler color change compared to their Russian counterparts. The initial belief that alexandrite was more abundant than pearls led to its adoption as a June birthstone, replacing the pearl in some circles, though this is no longer the case given the stone’s continued rarity.
Geological Formation and Sources
Alexandrite is a variety of chrysoberyl, a beryllium aluminum oxide mineral (BeAl₂O₄). The distinctive color change is attributed to the presence of chromium impurities within the crystal structure. The combination of beryllium, aluminum, oxygen, and chromium under specific geological conditions is exceptionally rare, contributing to the gemstone’s scarcity.
The original and most highly prized alexandrite originated in the Ural Mountains of Russia. These deposits, discovered in the 19th century, are now largely exhausted. Today, alexandrite is sourced from several locations, including Brazil, Sri Lanka, and East Africa. While these sources yield alexandrite, the color change is often less pronounced than that of the Russian stones. The formation of alexandrite requires unique geological processes, typically occurring in metamorphic rocks rich in beryllium.
Gemological Properties
Alexandrite possesses a unique combination of gemological properties that contribute to its desirability. Its hardness measures 8.5 on the Mohs scale, making it relatively durable – softer than sapphire but harder than garnet. This hardness allows it to withstand wear and tear, making it suitable for jewelry.
The most defining characteristic of alexandrite is its pleochroism, the ability to exhibit different colors when viewed from different angles. This phenomenon, combined with its color-changing ability, sets it apart from other gemstones. Under daylight or fluorescent light, alexandrite typically appears bluish-green to greenish-blue. However, when exposed to incandescent light, it transforms to purplish-red or reddish-purple. The intensity of this color change is a key factor in determining the stone’s value; a more complete and dramatic shift commands a higher price.
Most alexandrite stones are relatively small, typically weighing less than five carats. Larger stones with a strong color change are exceptionally rare and highly valuable. The gemstone is transparent, and its clarity can vary.
Here's a table summarizing key gemological properties:
| Property | Value |
|---|---|
| Mineral | Chrysoberyl |
| Chemical Formula | BeAl₂O₄ |
| Hardness (Mohs) | 8.5 |
| Color Change | Green to Red/Purple |
| Pleochroism | Present |
| Typical Size | < 5 carats |
Symbolism and Metaphysical Beliefs
Throughout history, alexandrite has been imbued with various symbolic meanings. In Russia, it was associated with good fortune and long life. More recently, alexandrite has been believed to strengthen intuition and creativity, aiding concentration and bringing good omens to the wearer.
The gemstone’s color-changing nature has also been interpreted symbolically, often likened to the complexities of love – presenting different facets depending on the perspective. Presenting alexandrite as a gift is considered a beautiful expression of affection. The stone is also associated with balance, self-esteem, and the ability to adapt to change.
Care and Cleaning
Due to its hardness of 8.5 on the Mohs scale, alexandrite is relatively durable. However, it is still susceptible to scratches and damage from harsh impacts. To maintain its brilliance, alexandrite jewelry should be cleaned regularly with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and harsh chemicals, as these can damage the stone. It is also advisable to remove alexandrite jewelry before engaging in strenuous activities to prevent scratches or chipping. Storage should be in a soft cloth or jewelry box to protect it from abrasion.
Conclusion
Alexandrite remains a captivating and highly sought-after gemstone, celebrated for its unique color-changing ability, historical significance, and relative rarity. From its discovery in the Ural Mountains of Russia and its association with the Imperial family to its modern status as a June birthstone, alexandrite continues to fascinate gemstone enthusiasts and jewelry lovers alike. Its enduring appeal lies in its ability to embody both beauty and mystery, making it a truly exceptional and cherished gem.