June is one of the few months with three recognized birthstones: pearl, moonstone, and alexandrite. While pearls offer classic luster and moonstone displays a mystical glow, alexandrite stands apart as one of the world's most extraordinary and valuable gemstones. Renowned for its dramatic and mysterious color-changing ability, this rare variety of chrysoberyl has captivated collectors and connoisseurs since its discovery in the 19th century. Its unique optical phenomenon, which renders it a vivid green in natural daylight and a rich red under incandescent light, has earned it the poetic moniker, "emerald by day, ruby by night."
The value of alexandrite is not merely a matter of aesthetics; it is driven by profound rarity and a geological history that confined its finest specimens to a single, remote region for decades. As one of the most expensive birthstones on the market, fine alexandrite can command prices exceeding $30,000 per carat, rivaling the finest rubies and sapphires. This article provides a detailed exploration of June's most valuable birthstone, examining its geological origins, unique gemological properties, the factors that determine its exceptional market value, and the lore that has grown around its enigmatic presence.
The Discovery and History of Alexandrite
The history of alexandrite is relatively modern compared to other ancient gemstones like emerald or ruby. Its story begins in the Ural Mountains of Russia in the early 1830s. According to historical accounts, the gem was first discovered by Finnish-born mineralogist Nils Gustaf Nordenskiöld on the birthday of the future Russian Tsar, Alexander II. The stone's red and green colors mirrored the old imperial Russian military colors, leading to its naming in the tsar's honor. This discovery cemented its place as a national treasure of Russia, and for many years, the finest gemstones were sourced exclusively from the Ural Mountains.
It wasn't until thirty years later, in the early 1860s, that other deposits of alexandrite were found in India, Burma, and Brazil. While these new sources provided additional material, the gemstone remains exceptionally rare. The original Russian deposits, which produced the most sought-after stones with the most dramatic color change, are now largely depleted. As noted in gemological literature, despite the discovery of these other deposits, alexandrite is still considered extremely rare, making it one of the world's most expensive gemstones. This enduring scarcity is a primary driver of its value and desirability in the fine jewelry market. The stone's relatively recent discovery means it lacks the deep-rooted ancient lore associated with many other gems, but its own history is rich with tales of imperial favor and geological wonder.
The Alexandrite Effect: A Marvel of Optics
The defining characteristic of alexandrite, and the source of its mystique, is its powerful color change. This phenomenon is a result of a rare confluence of its chemical composition and the physics of light. The gemstone is a variety of chrysoberyl, an aluminum oxide (BeAl₂O₄) with a hardness of 8.5 on the Mohs scale, making it exceptionally durable for jewelry. The crucial element that enables the color change is trace amounts of chromium (Cr³⁺) substituting for aluminum in the crystal structure. Chromium is the same element that gives emeralds their green color, but its interaction with the chrysoberyl host crystal is unique.
The scientific explanation for this "alexandrite effect" lies in how the gemstone absorbs and reflects different wavelengths of the visible light spectrum. The chromium ions in the crystal absorb specific portions of light, creating a "window" in the yellow-green part of the spectrum. In natural daylight, which is rich in green and blue wavelengths, the alexandrite reflects these colors, appearing green to the human eye. Under the incandescent light of a lamp or candle, which is dominated by red and yellow wavelengths, the stone's absorption window shifts. With less green light available to be reflected, the gem instead reflects the red rays present in the light source, causing it to appear red or pink.
This precise balance of light absorption is incredibly rare in nature. The gem must be "just right" in its chemical makeup for the effect to be noticeable. The color change is not a subtle shift but a dramatic transformation from a vibrant, emerald-like green to a rich, ruby-like red. This duality makes alexandrite a favorite among gemologists and collectors, as it is essentially two gems in one.
Gemological Properties and Identification
Beyond its color-changing ability, alexandrite possesses a set of distinct gemological properties that define its identity and value. Understanding these characteristics is essential for identifying the genuine stone and appreciating its quality.
- Chemical Composition: Alexandrite is a member of the chrysoberyl family, with the chemical formula BeAl₂O₄. The presence of chromium is what makes it alexandrite; without it, the stone would simply be a colorless or yellow chrysoberyl.
- Hardness and Durability: With a rating of 8.5 on the Mohs scale, alexandrite is one of the hardest and most durable gemstones. This exceptional hardness, second only to diamond among birthstones, makes it an excellent choice for all types of jewelry, including rings and bracelets that are subject to daily wear. It is resistant to scratching and abrasion, ensuring its beauty can be preserved for generations with proper care.
- Refractive Index and Crystal System: As a member of the chrysoberyl family, it has a refractive index of approximately 1.74-1.76. It crystallizes in the orthorhombic system. While these technical details are primarily of interest to gemologists, they are fundamental for proper identification and grading.
- Clarity and Inclusions: Like many fine gemstones, alexandrite often contains inclusions. While flawless stones are the most valuable, some inclusions are acceptable and can even serve as identification markers. However, significant inclusions that affect the stone's clarity or transparency will lower its value.
- Cut: Due to the importance of the color change, alexandrite is almost always cut to maximize this effect. The orientation of the cut is critical to display the dramatic shift from green to red. Common cuts include oval, cushion, and emerald cuts, which allow for a large table to showcase the stone's color.
Market Value: Why is Alexandrite So Expensive?
Alexandrite's position as one of the most expensive birthstones is a direct result of a powerful combination of extreme rarity, strong market demand, and its unique, untreated beauty. Its price per carat can be staggering, easily surpassing that of most other colored stones.
Rarity as the Primary Driver
The primary factor driving the price of alexandrite is its profound rarity. The finest and most famous alexandrites came from the Ural Mountains of Russia. These deposits, which produced stones with the most intense and dramatic color change, are now largely exhausted. While secondary deposits in India, Brazil, and other locations exist, the material from these localities is generally not considered to be of the same caliber as the original Russian gems. The color change in non-Russian stones is often less dramatic, and the stones themselves are smaller and less saturated.
The gemological community widely acknowledges this scarcity. High-quality natural alexandrite, particularly with a strong, clean color shift and over one carat in size, is exceptionally rare on the market. This scarcity is not a manufactured illusion but a genuine reflection of limited geological supply. As one source notes, "Stones like alexandrite and natural rubies are far scarcer than amethyst or citrine, leading to higher prices."
The Impact of Treatments and Enhancements
In the world of gemstones, treatments can significantly impact value. Alexandrite is almost always untreated. Heat treatment, which is common for sapphires and rubies to improve their color, is not effective for alexandrite because its color is derived from trace chromium, which is a fundamental part of the crystal structure. Similarly, clarity enhancements like fracture filling are not typically used on alexandrite. This lack of common treatments means that what you see is what you get—a naturally beautiful gemstone. Gemstones that are untreated or naturally vibrant are inherently more valuable. The fact that fine alexandrite requires no enhancement to achieve its spectacular appearance adds to its prestige and market value.
Market Demand and Investment Potential
While alexandrite is not as widely known to the general public as diamond or ruby, its fame within gemstone circles is immense. For serious collectors, connoisseurs, and investors, alexandrite is a prized asset. Its rarity ensures that it holds its value exceptionally well. Unlike more common gems whose prices can fluctuate with large new discoveries, the limited supply of fine alexandrite creates a stable and appreciating market.
The demand is for top-tier material. The price ranges for alexandrite vary dramatically based on quality. Lower-quality stones with a weak color change or significant inclusions can be found for a few thousand dollars per carat. However, for top-quality stones with a strong, distinct color change, clean clarity, and desirable size, the prices are astronomical. According to market analysis, high-quality alexandrite can range from $12,000 to over $35,000 per carat, with some exceptional Russian specimens fetching even higher prices at auction. This places it firmly in the same investment category as the "big three" of colored gemstones: ruby, sapphire, and emerald.
Alexandrite in the Hierarchy of Birthstones
When evaluating the worth of birthstones, alexandrite consistently ranks near the top. In a comparative ranking of birthstones from most to least expensive, alexandrite is positioned just below the "big three" (Diamond, Ruby, Emerald) and above Sapphire. One source places the average price range for alexandrite at $2,500-$3,000 per carat, while another, focusing on top-tier quality, cites a range of $12,000-$35,000+ per carat. This discrepancy highlights the vast quality differences in the market. For a standard commercial grade, it may be priced lower, but for gem-quality material suitable for fine jewelry, it is one of the most valuable birthstones available.
Symbolism and Metaphysical Beliefs
As a relatively modern gemstone, alexandrite does not have a long history of lore like amethyst or turquoise. Its symbolism is therefore more contemporary, derived from its unique physical properties. The most prominent meaning associated with alexandrite is balance. Its dramatic shift between two distinct colors—green and red—is seen as a representation of the balance between the physical and spiritual worlds, or the conscious and subconscious minds. It is believed to help its wearer navigate life's changes with grace and optimism.
Because it was discovered on the birthday of a Russian tsar, it has also come to symbolize good fortune and long life. The duality of its nature is thought to bring together the intellectual and the emotional, fostering creativity and imagination. Some believe that alexandrite can stimulate intuition and psychic abilities, making it a stone of mystics and seers. For those born in June, wearing alexandrite is said to enhance self-esteem and bring about a sense of inner harmony and confidence. Its association with joy and good luck makes it a meaningful gift, not just for birthdays but for other significant life events.
Care and Cleaning of Alexandrite Jewelry
Given its exceptional hardness and durability, alexandrite is relatively easy to care for, making it a practical choice for all types of jewelry. Its 8.5 rating on the Mohs scale means it is highly resistant to scratching and everyday wear. However, like all fine jewelry, it benefits from proper care to maintain its brilliance and longevity.
Cleaning: The safest way to clean alexandrite is with warm, soapy water and a soft brush, such as a baby toothbrush. Gently scrub the stone and its setting to remove any accumulated oils, dirt, or lotions. Rinse thoroughly with clean water to ensure no soap residue remains, which can dull its appearance. Avoid using harsh chemicals, bleach, or strong detergents, as these can potentially damage the metal setting or, in rare cases, affect any treatments on the stone (though alexandrite is rarely treated). Ultrasonic cleaners are generally safe for alexandrite itself due to its durability, but they should be used with caution if the stone is set in a delicate or porous mounting. Steam cleaning is also acceptable, but be mindful of thermal shock if the stone has any significant, large fractures.
Storage: When not being worn, store your alexandrite jewelry separately from other pieces. Because of its hardness, it can easily scratch softer gemstones like pearl, opal, or moonstone (which are also June birthstones). It is best to keep it in a soft cloth pouch or a lined jewelry box with individual compartments.
Handling and Protection: While alexandrite is tough, it is not indestructible. A hard blow along its cleavage planes (though chrysoberyl has poor cleavage) could potentially cause it to chip or fracture. It is wise to remove alexandrite jewelry before engaging in heavy physical activity, sports, or manual labor. Regular check-ups with a professional jeweler are also recommended to ensure the stone's setting remains secure.
Conclusion
Alexandrite is a gemstone that embodies the pinnacle of nature's artistry and rarity. Its captivating color-change ability, shifting from a lush green to a vibrant red, sets it apart from all other gems and has rightfully earned it the title of "emerald by day, ruby by night." This remarkable phenomenon, combined with its exceptional hardness and the mystique of its Russian imperial origins, elevates it to the status of a true collector's gem.
The value of alexandrite is a direct reflection of its scarcity. With the original Russian mines largely depleted and new sources producing material that rarely matches the quality of the originals, fine alexandrite remains one of the most difficult gemstones to find on the market. Consequently, it commands some of the highest prices per carat among all colored stones, placing it in the upper echelon of the birthstone hierarchy. For those born in June, alexandrite offers more than just a beautiful piece of jewelry; it is a symbol of balance, good fortune, and a tangible connection to one of the most fascinating stories in the world of gemology. Its enduring appeal and investment potential ensure that this rare and enigmatic gem will continue to fascinate and delight for generations to come.