The concept of birthstones, where a specific gemstone is assigned to each month of the year, has a rich and varied history. For the month of June, two distinct gemstones are recognized in the modern birthstone chart: the classic, organic pearl and the rare, color-changing alexandrite. Both stones carry deep historical significance and unique gemological properties, making them cherished choices for personal jewelry. This article explores the origins, lore, geological formation, and practical care of June's birthstones, drawing from historical records and gemological standards to provide a detailed overview for enthusiasts and collectors alike.
The Historical Journey to a Modern Standard
The tradition of linking specific stones to months of the year is believed to have ancient roots. One of the earliest and most influential references is the breastplate of Aaron, as described in the Old Testament of the Bible. This ceremonial garment, worn by the High Priest of the Israelites, was adorned with twelve gemstones, each representing one of the twelve tribes of Israel. The first-century Jewish historian Josephus was among the first to propose a connection between these twelve stones, the twelve months of the year, and the twelve signs of the zodiac. However, historical interpretations have varied significantly; Josephus himself provided two different lists of the stones on the breastplate, highlighting the lack of a singular, definitive ancient standard.
For centuries following, various lists of birthstones evolved, often influenced by regional availability, cultural beliefs, and commercial interests. These are often referred to as "traditional" birthstones. It wasn't until the early 20th century that a concerted effort was made to create a standardized list. In 1912, the (American) National Association of Jewelers, now known as the Jewelry Industry Council of America, convened to establish an official list. This list was created to bring consistency to the industry and the public, providing a clear guide for jewelers and consumers. The initial 1912 list designated pearl as the primary birthstone for June.
The standardization process, however, did not end there. The list has been updated several times to reflect new discoveries, market trends, and consumer preferences. In 1952, the Jewelry Industry Council of America updated the list, adding alexandrite as an alternative birthstone for June. This addition acknowledged the historical and gemological significance of alexandrite, a gem first discovered in the 1830s. Further updates included the addition of tanzanite to December in 2002 by the American Gem Trade Association. Today, the modern birthstone list for June includes pearl, moonstone, and alexandrite, offering a range of choices from organic and traditional to rare and color-changing.
Geological Formation and Sources
The two birthstones for June could not be more different in their origin. Pearls are organic gems, formed within living mollusks, while alexandrite is a mineralogical species, a variety of chrysoberyl formed deep within the Earth's crust.
The Organic Origin of Pearls
A pearl is a lustrous, organic gem created when an irritant, such as a grain of sand or a microscopic parasite, enters the soft tissue of a mollusk (an oyster or mussel). To protect itself, the mollusk secretes layers of nacre, a composite material made of aragonite (a form of calcium carbonate) and conchiolin (an organic protein), around the irritant. Over time, these layers build up to form a pearl. The quality of a pearl is determined by the smoothness of its surface, the intensity and uniformity of its luster, and its shape. While natural pearls are exceptionally rare and valuable, the vast majority of pearls on the market today are cultured, a process where humans intentionally introduce an irritant to stimulate nacre production. Sources for pearls are found worldwide, with major production centers in Japan, China, Australia, and the South Sea.
The Terrestrial Origin of Alexandrite
Alexandrite is a rare and highly prized variety of the mineral chrysoberyl. Its formation requires a unique geological environment. Chrysoberyl (BeAl₂O₄) is a beryllium-aluminum oxide mineral that crystallizes under high temperature and pressure. The defining characteristic of alexandrite—its dramatic color change from green in daylight to red in incandescent light—is caused by the presence of chromium (Cr³⁺) ions substituting for aluminum in the crystal lattice. This specific trace element, combined with the stone's chemical composition and the precise wavelength of light, creates the optical phenomenon known as pleochroism, which results in the observed color change.
The primary and most historically significant source of alexandrite is the Ural Mountains in Russia. The stone was discovered there in the 1830s and named after the future Tsar Alexander II. The Russian deposits, however, are largely depleted. Today, alexandrite is also found in Brazil, Sri Lanka, East Africa, and India, though the finest material with the most pronounced color change remains exceptionally rare and commands premium prices.
Gemological Properties: A Tale of Two Stones
The physical and optical properties of pearl and alexandrite are fundamental to their identity, value, and care.
Pearl: The Organic Luster
Pearls are unique among gemstones for their organic origin and non-crystalline structure. Their hardness is relatively low on the Mohs scale, typically ranging from 2.5 to 4.5, making them susceptible to scratching and abrasion. They lack the typical crystalline structure of minerals, which affects their durability. The most prized pearls exhibit a deep, satiny luster, which is a measure of the intensity and quality of light reflected from the pearl's surface. This luster is a direct result of the nacre's layered structure. Pearls come in a wide array of natural colors, including white, cream, pink, silver, gold, and black, with the most valuable being the rare, natural black pearls from the South Sea.
Alexandrite: The Color-Changing Chrysoberyl
Alexandrite is a member of the chrysoberyl family, which also includes the mineral chrysoberyl itself and the cat's-eye variety. As a chrysoberyl, it is a very durable gemstone, with a Mohs hardness of 8.5, making it suitable for all types of jewelry, including rings, where it can withstand daily wear. Its specific gravity is relatively high, and it has a refractive index that contributes to its brilliance. The most celebrated property of alexandrite is its pleochroism, specifically its dramatic color change. In natural daylight or fluorescent light, it appears a vivid blue-green to greenish-blue. Under the warm, incandescent light of a lamp or candle, it transforms to a soft, raspberry red or purplish-red. The quality of this color change is a primary factor in determining an alexandrite's value; the more distinct and complete the shift, the more valuable the stone.
Comparative Properties of June's Birthstones
| Property | Pearl (Cultured) | Alexandrite |
|---|---|---|
| Mineral Species | Organic (Nacre) | Chrysoberyl (BeAl₂O₄) |
| Hardness (Mohs) | 2.5 - 4.5 | 8.5 |
| Key Characteristic | Luster, Surface Quality | Color Change (Green to Red) |
| Typical Colors | White, Cream, Pink, Black | Green (Daylight) / Red (Incandescent) |
| Chemical Formula | CaCO₃ (Aragonite) | BeAl₂O₄ with Cr³⁺ |
Symbolism and Metaphysical Beliefs
Throughout history, both pearls and alexandrite have been imbued with deep symbolic meaning and metaphysical properties.
The Pearl: Purity and Wisdom
Pearls have long been associated with purity, innocence, and wisdom. In many cultures, they are seen as symbols of the moon, with their soft, glowing luster. In the Middle Ages, pearls were worn by royalty and the clergy to signify their status and piety. They were often thought to attract good fortune and protect the wearer from harm. In some Eastern traditions, pearls are linked to the planet Venus and are believed to promote love, harmony, and emotional balance. The pearl's formation within the mollusk is sometimes seen as a metaphor for the hidden wisdom that comes from life's irritants and challenges.
Alexandrite: A Stone of Good Fortune
The discovery of alexandrite in the Ural Mountains of Russia was shrouded in legend. It was said that the stone was found by miners on the future Tsar's birthday, and its red and green colors mirrored the old imperial Russian military colors. This serendipitous discovery led to its reputation as a stone of immense good luck and fortune. In Russian folklore, alexandrite was believed to bring balance between the physical and spiritual worlds. Its color change was seen as a metaphor for the duality of life—joy and sorrow, day and night. It is often associated with creativity, intuition, and the ability to see both sides of any situation.
Care and Maintenance
Due to their vastly different physical properties, the care required for pearls and alexandrite is distinctly different.
Caring for Pearls
Pearls are delicate and require gentle handling. Their low hardness makes them prone to scratches from harder materials, including other gemstones and even dust. It is advisable to store pearls separately in a soft cloth pouch or lined jewelry box. They should be the last item you put on when dressing and the first to be removed, as chemicals in cosmetics, hairspray, and perfumes can damage the nacre's luster. Pearls should be cleaned with a soft, damp cloth after each wear to remove body oils and residue. They should never be exposed to harsh chemicals, ultrasonic cleaners, or steam.
Caring for Alexandrite
Alexandrite's high hardness (8.5 on the Mohs scale) makes it a durable and practical choice for everyday jewelry. It is resistant to scratching and can be cleaned with standard jewelry cleaning methods. Warm, soapy water and a soft brush are effective for removing dirt and oils. While it is relatively tough, it is still a gemstone and should be protected from sharp blows and extreme temperature changes, which could potentially cause fractures. Ultrasonic cleaners are generally safe for untreated alexandrite, but caution is advised for stones that may have undergone fracture-filling treatments.
Conclusion
The month of June is uniquely represented by two gemstones that offer a compelling contrast: the organic, lustrous pearl and the mineralogical, color-changing alexandrite. The pearl, with its ancient origins in the breastplate of Aaron and its modern status as a classic birthstone, symbolizes purity and wisdom. Its formation within a living creature makes it a unique gem in the mineral world. Alexandrite, a more recent addition to the birthstone list, captivates with its rare and dramatic optical phenomenon, embodying good fortune and balance. Both stones have rich histories, distinct gemological properties, and specific care requirements. Whether one is drawn to the timeless elegance of the pearl or the mesmerizing transformation of the alexandrite, June's birthstones provide a wealth of choices for personal adornment and meaningful gifting, each carrying a legacy of beauty and significance.