Alexandrite stands as one of the most remarkable and valuable gemstones in the world, holding a unique position among birthstones as the primary gem for June, alongside pearl and moonstone. Its exceptional color-changing properties, coupled with a fascinating history and relative scarcity, contribute to its high market value, ranging from $15,000 to $70,000 per carat. This article will delve into the history, geological origins, gemological properties, and significance of this captivating gem, drawing solely from available sources.
A Discovery Linked to Royalty
The story of alexandrite’s discovery is interwoven with Russian imperial history. The gemstone was first found in 1830 in the Ural Mountains of Russia. Legend states that this discovery coincided with the birthday of Czar Alexander II, then heir to the throne, leading to the gem being named in his honor. The stone’s distinctive red and green hues also resonated with the colors of the Russian military, solidifying its status as the national stone of Russia. This association with royalty and national identity immediately elevated alexandrite’s prestige.
The Science of Color Change
What truly sets alexandrite apart is its dramatic color-changing ability. This phenomenon, known as the alexandrite effect, causes the gemstone to appear bluish-green in daylight and purplish-red under incandescent light. This remarkable characteristic is due to the gem’s chemical composition and its ability to absorb different wavelengths of light under varying light sources. Alexandrite is a variety of the mineral chrysoberyl, and this unique optical property is relatively rare within the chrysoberyl family. Some jewelers playfully describe it as an “emerald by day and a ruby by night,” highlighting the dramatic shift in appearance.
Geological Formation and Global Sources
Alexandrite forms in specific geological environments, typically in metamorphic rocks rich in beryllium. The initial discovery in the Ural Mountains of Russia established the region as a primary source for many years. However, the sources available today are more diverse. While the Ural Mountains remain historically significant, alexandrite is now also found in countries like Brazil, Sri Lanka, Myanmar, and Africa. The availability of alexandrite from these locations contributes to the range in quality and price observed in the market.
Gemological Characteristics
Alexandrite is a member of the chrysoberyl family, possessing a chemical formula that includes beryllium, aluminum, and oxygen. Its hardness ranges from 6.5 to 7 on the Mohs scale, indicating a good level of durability suitable for jewelry. This hardness makes it resistant to scratching from everyday wear, though care should still be taken to avoid damage. The gem exhibits a vitreous luster, contributing to its brilliance. While color change is the defining characteristic, the intensity and clarity of the color shift significantly impact the stone’s value.
Symbolism and Significance
While the provided sources do not detail extensive historical symbolism, alexandrite’s association with Russian royalty inherently imbues it with connotations of power, good fortune, and nobility. As a birthstone for June, it is often gifted to symbolize preciousness and affection. The gemstone’s rarity and unique properties also contribute to its perceived value and desirability. Pearls, also a June birthstone, are described as the “Queen of Gemstones,” often gifted by kings to symbolize esteem, while turquoise, another December birthstone, signifies value and rarity.
Comparing Alexandrite to Other Birthstones
Alexandrite’s value significantly surpasses that of many other birthstones. It is notably more expensive than emerald, ruby, and sapphire – collectively known as the “Big Three” of precious stones. While ruby, another member of the corundum family alongside sapphire, is highly valued for its red hue, alexandrite’s color-changing ability sets it apart. Diamonds, the April birthstone, are renowned for their brilliance and hardness (rating 10 on the Mohs scale), but lack the dynamic color play of alexandrite. Aquamarine, the March birthstone, with a hardness of 7.5-8, offers a beautiful blue-green hue but does not possess the same level of rarity or dramatic optical effect. Tanzanite, a December birthstone, is also rare and displays pleochroism (different colors viewed from different angles), but its color change is not as pronounced as alexandrite’s.
Other Notable Birthstones and Their Properties
Several other gemstones hold significance as birthstones, each with unique characteristics. Sapphire, the September birthstone, boasts a remarkable hardness of 9 on the Mohs scale and is found in a variety of colors, including blue, yellow, orange, and green. Opal, an October birthstone, is known for its play-of-color, a captivating display of iridescent hues. Emerald, the May birthstone, ranges between 7.5 to 8 on the Mohs scale and is prized for its vibrant green color. Turquoise, a December birthstone, has been valued for thousands of years and is found in shades of blue, blue-green, and green, with a hardness of 5 to 6. Zircon, also a December birthstone, exhibits a hardness between 6 and 7.5 and is available in a range of colors, including blue, red, and yellow.
Care and Maintenance
Due to its hardness of 6.5-7 on the Mohs scale, alexandrite is relatively durable but still requires careful handling. It is susceptible to scratching from harder materials and should be stored separately from other jewelry to prevent abrasion. Cleaning can be performed with warm, soapy water and a soft brush. Avoid harsh chemicals or ultrasonic cleaners, as these may damage the gemstone. Regular cleaning will help maintain its brilliance and preserve its color-changing properties.
The Market and Scarcity
The closure of the Argyle diamond mine in Western Australia in 2020, a primary source of pink diamonds, has exacerbated the scarcity of certain colored gemstones, including pink diamonds. This event underscores the impact of supply and demand on gemstone prices. Similarly, the limited availability of high-quality alexandrite contributes to its high market value. The unique geological conditions required for its formation and the limited number of viable mining locations ensure that alexandrite will remain a rare and sought-after gemstone.
Conclusion
Alexandrite is a truly exceptional gemstone, distinguished by its captivating color-changing properties, historical significance, and relative scarcity. From its discovery in the Ural Mountains of Russia and its association with Czar Alexander II to its current status as a highly prized birthstone for June, alexandrite continues to fascinate and inspire. Its unique combination of scientific properties, historical lore, and aesthetic appeal solidifies its position as one of the most valuable and alluring gemstones in the world.