June is one of the few months in the birthstone calendar that offers a choice of three distinct gemstones: pearl, moonstone, and alexandrite. While pearls and moonstone have long-standing traditions, alexandrite is a relatively modern addition. This rare gemstone stands out for its extraordinary ability to change color under different light sources—green in daylight and red or purple in artificial light. Known as the "emerald by day and ruby by night," alexandrite has captured the imagination of gem lovers and collectors since its discovery in the 19th century.
This article delves into the geological, historical, and cultural significance of alexandrite, exploring its formation, physical properties, and symbolic meaning. It also examines the gemstone’s journey from a hidden treasure in the Russian Urals to a globally recognized birthstone and anniversary gem. Whether you are a gemology student, a jewelry buyer, or simply curious about the world of birthstones, this guide will provide a comprehensive overview of this captivating June birthstone.
History and Lore
The history of alexandrite is as intriguing as the gemstone itself. Discovered in 1834 in the emerald mines of the Ural Mountains in Russia, alexandrite was named in honor of Tzar Alexander II, who was celebrating his 16th birthday at the time. The gemstone quickly became a symbol of Russian prestige, particularly because its color change mirrored the red and green of the Russian military and imperial colors.
The discovery of alexandrite is credited to Finnish mineralogist Nils Gustaf Nordenskiöld, though some sources also attribute it to Russian mineralogist Count L.A. Perovskii or German professor Gustav Rose. What is clear is that the miners initially mistook the stones for emeralds due to their vivid green color. It was only when they observed the stones glowing red in the light of their campfire that they realized they had uncovered a new and extraordinary gem.
Alexandrite soon gained royal favor, with Tzar Alexander II reportedly wearing an alexandrite ring as a personal talisman. The gemstone became a symbol of good fortune and national pride, and its rarity only enhanced its prestige. By the late 19th century, however, the Russian mines were nearly exhausted, and alexandrite was rediscovered in other parts of the world, including Brazil, Sri Lanka, and Zimbabwe. These new sources have helped to keep alexandrite in the spotlight, though Russian alexandrite remains the most prized for its intense color change and historical significance.
Geological Formation and Sources
Alexandrite is a rare variety of the mineral chrysoberyl, which is composed of beryllium aluminum oxide (BeAl₂O₄). What sets alexandrite apart is its unique ability to change color, a property known as color change. This effect is due to the presence of trace amounts of chromium in the crystal structure. Chromium absorbs certain wavelengths of light, causing the gemstone to appear green in daylight (which contains more blue light) and red in incandescent light (which contains more yellow and red light).
Alexandrite is typically found in metamorphic rocks, particularly in granitic pegmatites and in the residual deposits left behind by weathering. The original source of alexandrite was the Ural Mountains in Russia, where it was first discovered in 1834. However, by the 1890s, the Russian mines were nearly depleted. In the 20th century, new deposits were discovered in Brazil, where alexandrite is found in the state of Minas Gerais. Other notable sources include Sri Lanka, Madagascar, and Zimbabwe, where alexandrite is mined from alluvial deposits.
The rarity of alexandrite, particularly stones with a strong color change and high clarity, makes it one of the most valuable gemstones in the world. Stones over one carat with a pronounced color change are extremely rare, and large alexandrites are considered collector’s items. The size of alexandrite gems is typically limited, with most stones being less than five carats in weight. This scarcity has contributed to the gemstone’s mystique and high market value.
Gemological Properties
Understanding the physical and optical properties of alexandrite is essential for gemologists, jewelers, and collectors. The gemstone has a hardness of 8.5 on the Mohs scale, which makes it durable enough for everyday wear in jewelry. However, due to its rarity, alexandrite is often reserved for special pieces such as pendants, rings, and earrings.
The refractive index of alexandrite ranges from 1.74 to 1.78, and its specific gravity is approximately 3.73. These properties help in identifying alexandrite and distinguishing it from other color-changing gemstones such as sapphire or spinel. The most defining characteristic of alexandrite is its color change, which is measured by the difference in color between daylight and incandescent light. The most valuable alexandrites exhibit a dramatic shift from green to red or purple.
Alexandrite is typically cut in a modified brilliant or emerald cut to enhance its color change and brilliance. The cut also helps to minimize inclusions and maximize the gemstone’s clarity. Inclusions are relatively rare in alexandrite, but when present, they are often small and do not detract from the stone’s beauty.
The color change effect is best observed under natural daylight and incandescent light. Fluorescent lighting can also produce interesting effects, but the most striking transformation occurs in candlelight or warm white light. This property has made alexandrite a popular choice for evening wear and special occasions.
Symbolism and Metaphysical Beliefs
Alexandrite has long been associated with good fortune, protection, and emotional balance. In Russian folklore, it was believed that wearing alexandrite could bring prosperity and ward off misfortune. Some cultures also associate the gemstone with love and passion, particularly because of its red color in artificial light. The color change is seen as a metaphor for transformation and adaptability, making alexandrite a symbol of personal growth and resilience.
In modern metaphysical practices, alexandrite is considered a stone of balance and harmony. It is believed to help align the heart and mind, promoting emotional stability and clarity of thought. Some practitioners use alexandrite to enhance intuition and spiritual awareness, particularly during meditation or healing sessions. The gemstone is also said to stimulate creativity and imagination, making it a popular choice for artists and writers.
Alexandrite is associated with the zodiac signs of Gemini and Cancer, both of which are linked to June. For Geminis, alexandrite is believed to enhance adaptability and communication, while for Cancers, it is thought to promote emotional security and nurturing. These associations have contributed to the gemstone’s popularity as a birthstone and anniversary gift.
As the June birthstone, alexandrite is often given as a gift for the 55th wedding anniversary, symbolizing a long and prosperous union. Its rarity and unique properties make it a meaningful and memorable token of love and commitment.
Care and Cleaning
Due to its high value and delicate nature, alexandrite requires special care to maintain its beauty and longevity. While the gemstone is relatively hard (8.5 on the Mohs scale), it is not impervious to damage. Sharp blows can cause fractures, especially if the gemstone has inclusions or weaknesses in the crystal structure.
To clean alexandrite jewelry, it is best to use a soft cloth and mild soapy water. Ultrasonic cleaners can be used with caution, but they should be avoided if the gemstone has any surface fractures or inclusions that could trap water and cause damage. Steam cleaning is not recommended for alexandrite, as it can cause thermal shock and damage the gemstone.
When storing alexandrite jewelry, it should be kept in a soft pouch or a lined jewelry box to prevent scratches from harder gemstones such as diamonds or corundum. Alexandrite should also be stored separately from other gemstones that are prone to abrasion, as even small particles can cause scratches over time.
When wearing alexandrite, it is best to avoid exposing it to harsh chemicals or extreme temperatures. While the gemstone is relatively stable, prolonged exposure to heat or strong acids can affect its color change and clarity. It is also advisable to avoid wearing alexandrite during activities that involve rough handling or contact with abrasive surfaces.
By following these care and cleaning guidelines, alexandrite can retain its brilliance and beauty for many years, ensuring that this rare and captivating gemstone remains a treasured part of any jewelry collection.
Conclusion
Alexandrite is a gemstone of exceptional rarity, beauty, and historical significance. From its discovery in the Russian Urals to its modern status as a June birthstone and 55th anniversary gem, alexandrite has captivated the imagination of gem lovers for centuries. Its unique color-changing properties, combined with its rich symbolism and cultural lore, make it one of the most intriguing gems in the world.
Whether admired for its scientific properties, its historical associations, or its metaphysical significance, alexandrite continues to inspire and enchant. As a June birthstone, it represents a perfect blend of tradition and innovation, offering a unique and meaningful choice for those born in this month. With proper care and appreciation, alexandrite can remain a treasured heirloom for generations to come.