For individuals born on December 27th, the birthstone selection is uniquely abundant, featuring a trio of captivating gemstones: Tanzanite, Turquoise, and Zircon. Each of these gems possesses distinct characteristics, histories, and cultural significances that collectively embody the essence of December. While Tanzanite is a modern discovery celebrated for its vibrant blue and purple hues, Turquoise carries millennia of history as a protective talisman, and Zircon offers a dazzling array of colors with a rich geological legacy. This article provides a comprehensive exploration of these three gemstones, delving into their historical contexts, geological origins, gemological properties, and the symbolic meanings attributed to them, offering a detailed insight for gemstone enthusiasts, jewelry buyers, and students of gemology.
History and Lore
The historical journey of each gemstone reveals a tapestry of human interaction, from ancient civilizations to modern markets.
Tanzanite Tanzanite is a relatively recent addition to the world of gemstones. It was discovered in 1967 in Tanzania, a country from which it derives its name, specifically in the foothills of Mount Kilimanjaro. This gemstone is a variety of the mineral zoisite and is renowned for its vibrant blue and purple colors. Its discovery is a modern gemological event, placing it in stark contrast to the ancient origins of its December counterparts. As a birthstone, it represents transformation and new beginnings, reflecting its recent emergence into the gemological lexicon.
Turquoise In contrast to Tanzanite, Turquoise has been cherished for millennia. It is one of the oldest known gemstones in human history, with evidence of its use dating back to ancient Egypt, where it was worn as a protective talisman and a symbol of status. Its name is derived from the French "pierre turquoise," meaning "Turkish stone," as it was first brought to Europe from the mines of Persia (modern-day Iran) via Turkey. Throughout history, it has been revered by numerous cultures, including Native American tribes of the Southwestern United States, who have mined and worked with turquoise for centuries, embedding it deeply into their cultural and spiritual practices.
Zircon Zircon possesses a fascinating and sometimes misunderstood history. It is one of the oldest minerals on Earth, with some zircon crystals dating back billions of years. For centuries, it has been valued for its brilliance and fire, often confused with diamond due to its high refractive index. Historically, zircon was believed to promote honor and purity in the wearer. Its journey to becoming a modern birthstone is part of a broader evolution of birthstone lists, which have been formalized and updated over time by organizations like the American Gem Trade Association (AGTA) and the Jewelers of America (JA). While specific historical events for December 27th are not detailed in the sources, the inclusion of zircon in the December trio underscores its enduring appeal and its role in offering a variety of colors and styles for birthstone jewelry.
The modern classification of birthstones for December, which includes all three gems, was established to provide a wider range of color and style options. This evolution reflects a shift from a single stone per month to a more inclusive and flexible approach, allowing individuals to choose based on personal preference, aesthetic, or perceived metaphysical properties.
Geological Formation and Sources
Understanding the origin of these gemstones provides insight into their rarity and unique characteristics.
Tanzanite Tanzanite is a variety of the mineral zoisite. Its formation is geologically unique, occurring only in a small mining area in the Merelani Hills of Tanzania, near the foothills of Mount Kilimanjaro. This single-source origin makes it significantly rarer than diamonds, with geologists estimating that the current supply may be depleted within a few decades. The gemstone's vivid blue color is the result of specific geological conditions and heat treatment, which is a standard industry practice to enhance its natural hues.
Turquoise Turquoise is a hydrated phosphate of copper and aluminum, forming in arid regions where acidic, copper-rich water seeps through rocks containing aluminum and phosphorus. This process occurs in the earth's crust, creating nodules or veins. Major sources include the United States (particularly Arizona, Nevada, and New Mexico), Iran, China, Egypt, and Mexico. The color of turquoise ranges from sky blue to greenish hues, depending on the specific mineral content (copper for blue, iron for green) and the presence of the host rock, which often leaves a distinctive matrix pattern in the finished gem.
Zircon Zircon is a zirconium silicate (ZrSiO₄) and is a common mineral found in many types of rocks. It is highly resistant to weathering and is often found in placer deposits, which are sediments accumulated by water action. Significant sources include Australia (which produces a large portion of the world's gem-quality zircon), Cambodia, Sri Lanka, Thailand, and the United States. Zircon occurs in a variety of colors, including colorless (often called "Matura diamond"), blue, green, yellow, orange, and brown. The blue variety is particularly popular for December birthstones, though heat treatment is commonly used to achieve or enhance certain colors.
Gemological Properties
The physical and optical properties of these gems dictate their durability, appearance, and care requirements.
| Gemstone | Chemical Composition | Hardness (Mohs Scale) | Refractive Index | Key Optical Properties | Typical Colors |
|---|---|---|---|---|---|
| Tanzanite | Ca₂Al₃(SiO₄)₃(OH) (Zoisite variety) | 6.5 - 7 | 1.691 - 1.700 | Pleochroic (shows blue, violet, and burgundy from different angles) | Blue, Violet, Purple |
| Turquoise | Hydrated phosphate of copper and aluminum | 5 - 6 | 1.610 - 1.650 | Opaque, often with a waxy to vitreous luster | Sky blue to greenish-blue |
| Zircon | ZrSiO₄ | 6.5 - 7.5 | 1.92 - 2.01 | High refractive index and strong dispersion (fire) | Colorless, Blue, Yellow, Brown, Green |
Tanzanite Tanzanite is a relatively soft gemstone compared to others like sapphire or diamond, with a Mohs hardness of 6.5 to 7. This makes it susceptible to scratches and abrasion, requiring careful handling. Its most defining characteristic is its strong pleochroism, meaning it displays different colors when viewed from different crystal directions—typically blue, violet, and sometimes a reddish burgundy. This dynamic color play is a major factor in its appeal. Most tanzanite on the market has been heat-treated to enhance its blue and violet hues, a process that is permanent and stable.
Turquoise Turquoise is an opaque gemstone with a Mohs hardness of 5 to 6, making it relatively soft and porous. It is sensitive to heat, chemicals, and prolonged exposure to sunlight, which can cause fading or discoloration. Its color is determined by its chemical composition: copper produces the classic blue, while iron contributes to green tones. Many turquoise specimens contain a "matrix," which is the remnant of the host rock, creating intricate web-like patterns that are often prized by collectors and artisans.
Zircon Zircon is one of the hardest natural gemstones, with a Mohs hardness of 6.5 to 7.5, making it durable enough for everyday jewelry, though it can be brittle due to its crystal structure. Its most notable property is its high refractive index (1.92-2.01), which gives it exceptional brilliance and fire, often compared to that of a diamond. This high dispersion (the ability to split light into spectral colors) can create a dazzling sparkle. Blue zircon is typically heat-treated from brown zircon crystals, a process that is stable and widely accepted in the gem trade.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, these gemstones are imbued with symbolic meanings and metaphysical properties that resonate with wearers.
Tanzanite Tanzanite is often associated with qualities of clarity, calmness, and spiritual insight. It is believed to promote self-awareness and enlightenment, making it a fitting stone for personal growth and transformation. In terms of healing properties, it is said to have a soothing effect on the mind and body, helping to alleviate stress, anxiety, and emotional turmoil. Its vibrant colors are linked to the crown and throat chakras, facilitating communication and spiritual connection.
Turquoise As one of the most historically significant protective stones, Turquoise is widely linked to protection, good fortune, and healing. Across many cultures, it has been worn as an amulet to ward off negative energy and bring safety to travelers. It is also associated with balance, peace, and emotional stability. For many Native American cultures, turquoise is a sacred stone that represents the sky and water, symbolizing life, health, and protection from harm.
Zircon Zircon is associated with clarity, wisdom, and a sense of balance. It is believed to enhance mental clarity, promote self-confidence, and bring prosperity. Historically, it was thought to aid in sleep and protect against nightmares. The different colors of zircon carry their own subtle meanings; for example, blue zircon is linked to peace and tranquility, while golden zircon is associated with abundance and success.
The choice between these stones often comes down to personal resonance with their symbolic meanings, whether one seeks transformation (Tanzanite), protection (Turquoise), or clarity and balance (Zircon).
Care and Cleaning
Proper maintenance is essential to preserve the beauty and longevity of these gemstones, given their distinct physical properties.
Tanzanite Due to its moderate hardness and perfect cleavage in one direction, Tanzanite is relatively fragile. It is not recommended for rings or bracelets worn daily, where impact and abrasion are likely. It is better suited for earrings, pendants, or occasional-wear rings. Cleaning should be done with warm, soapy water and a soft brush. Avoid ultrasonic cleaners, steam cleaners, and sudden temperature changes, as these can cause cracking or fracturing.
Turquoise Turquoise requires the most careful handling among the three. Its porosity and softness make it vulnerable to damage from chemicals, cosmetics, and prolonged sunlight. To clean turquoise, use only a soft, dry cloth. If necessary, a slightly damp cloth can be used, but it must be dried immediately. Never use ultrasonic cleaners, steam, or harsh chemicals. It is advisable to remove turquoise jewelry before swimming, bathing, or applying lotions and perfumes.
Zircon While Zircon is harder and more durable than Tanzanite and Turquoise, it has perfect cleavage in two directions, making it susceptible to chipping if struck with force. It is generally safe for most jewelry types, including rings, but should be protected from hard blows. Cleaning can be done with warm, soapy water and a soft brush. Ultrasonic cleaners are generally safe, but caution is advised for stones with inclusions or fractures. Avoid sudden temperature changes to prevent potential cracking.
Conclusion
The birthstones for December 27th—Tanzanite, Turquoise, and Zircon—offer a remarkable diversity in origin, appearance, and meaning. From the ancient protective talisman of Turquoise to the modern, transformative allure of Tanzanite and the brilliant, balanced fire of Zircon, each gem provides a unique avenue for personal expression and connection to the natural world. Their selection is not merely a matter of tradition but an opportunity to choose a stone whose color, durability, and symbolism align with individual preferences and lifestyle. As the gemological community continues to celebrate these December gems, their legacy as birthstones for those born on the 27th remains a testament to the enduring beauty and significance of the mineral kingdom.