In the world of gemology, few months boast a birthstone trio as diverse and visually striking as December. While the modern birthstone list has evolved over time, December is uniquely associated with three distinct gemstones: the serene Blue Topaz, the rare Tanzanite, and the ancient Turquoise. Each stone carries its own unique history, geological origin, and symbolic meaning, offering a wide spectrum of choices for jewelry enthusiasts and those celebrating a December birthday. This article delves into the characteristics, lore, and craftsmanship behind these three captivating December birthstones, providing a comprehensive overview for gemstone lovers and collectors.
History and Lore
The journey of December’s birthstones is a fascinating blend of ancient tradition and modern gemological discovery. While the concept of birthstones can be traced back to the breastplate of the High Priest of ancient Israel, as described in the Book of Exodus, the modern list was standardized in 1912 by the American National Retail Jewelers Association (now Jewelers of America). Initially, the list included only Turquoise and Lapis Lazuli for December. Zircon was added in 1952, and the list was further updated in the 2000s to include Tanzanite and Blue Topaz, reflecting the gemstone industry's evolving landscape and the discovery of new sources.
Turquoise stands as the oldest member of this group, with a history spanning millennia. Its use in jewelry dates back to ancient Egypt, where it was revered for its protective qualities and vibrant color. The stone’s name is derived from the French pierre turquoise, meaning "Turkish stone," as it was transported to Europe through Turkish trade routes from the Persian Empire. For centuries, Turquoise has been a talisman for protection, good fortune, and spiritual grounding in cultures from the Native American tribes of the American Southwest to the nomadic tribes of Central Asia.
Blue Topaz, while less ancient in its historical record as a specific birthstone, has been valued for its clear, sky-blue hues. The stone’s name is believed to come from the Sanskrit word tapas, meaning "fire," which was likely a reference to the yellow Topaz variety. However, the brilliant blue stones we recognize today are typically the result of irradiation and heat treatment applied to colorless or pale yellow topaz. This process, which enhances the stone’s natural properties, has made Blue Topaz an accessible and popular gemstone for modern jewelry.
Tanzanite is the newest addition, a gemstone whose discovery is a relatively recent event in the annals of gemology. First found in the Merelani Hills of Northern Tanzania in 1967, this violet-blue gemstone was initially mistaken for sapphire. Its unique color, a result of specific trace elements in its crystal structure, and its scarcity have made it one of the most sought-after stones of the late 20th and early 21st centuries. In 2002, the American Gem Trade Association (AGTA) added Tanzanite to the official birthstone list for December, cementing its status as a modern classic.
Geological Formation and Sources
The origins of these gemstones are as varied as their appearances, each forming under distinct geological conditions and sourced from specific regions of the world.
Turquoise is a hydrous phosphate mineral, formed in the presence of water in arid regions where copper-rich groundwater interacts with aluminum and phosphorus-bearing rocks. This process occurs in secondary deposits, such as veins and nodules within host rock. The most renowned sources of high-quality Turquoise are in the United States, particularly in Arizona, Nevada, and New Mexico. The American Southwest is famous for its variety of Turquoise, including the distinctive spiderweb matrix patterns found in stones from the Sleeping Beauty mine in Arizona. Internationally, Iran (formerly Persia) is another historic source of exceptionally fine, sky-blue Turquoise.
Blue Topaz is a silicate mineral, specifically a variety of the mineral topaz. It forms in igneous rocks, particularly in pegmatites and high-temperature veins. While topaz is found in many locations worldwide, the vast majority of the vibrant blue Topaz on the market today is sourced from Brazil. The natural, pale blue topaz is often subjected to a process of irradiation followed by heat treatment to achieve the deeper, more desirable shades of Swiss Blue, London Blue, and Sky Blue. This treatment is permanent and is a standard industry practice, making the gemstone both beautiful and durable for jewelry.
Tanzanite is a variety of the mineral zoisite, specifically the blue to violet-blue form. Its formation is geologically unique; it is found in a single, small mining area in the Merelani Hills of Tanzania, near the base of Mount Kilimanjaro. This locality is the only known commercial source of Tanzanite in the world, making it thousands of times rarer than diamond. The gemstone is formed through a complex geological process involving heat and pressure from tectonic activity in the East African Rift. Due to its limited geographic source, Tanzanite is often marketed as "a generation's worth of gemstone," emphasizing its finite availability and increasing value over time.
Gemological Properties
Understanding the physical and chemical properties of these gemstones is crucial for appreciating their durability, care requirements, and value in jewelry. The following table summarizes the key gemological characteristics of the three December birthstones, based on standard gemological data.
| Property | Blue Topaz | Tanzanite | Turquoise |
|---|---|---|---|
| Mineral Family | Silicate (Topaz) | Silicate (Zoisite) | Phosphate (Hydrous Copper Aluminum Phosphate) |
| Chemical Formula | Al₂SiO₄(F,OH)₂ | Ca₂Al₃(SiO₄)₃(OH) | CuAl₆(PO₄)₄(OH)₈·4H₂O |
| Crystal System | Orthorhombic | Orthorhombic | Triclinic |
| Hardness (Mohs Scale) | 8 | 6.5 - 7 | 5 - 6 |
| Refractive Index | 1.609 - 1.629 | 1.691 - 1.700 | 1.610 - 1.650 |
| Specific Gravity | 3.49 - 3.57 | 3.35 | 2.60 - 2.90 |
| Luster | Vitreous | Vitreous to Greasy | Waxy to Vitreous |
| Durability & Care | Very good (8 on Mohs). Resistant to scratching, but can be brittle due to cleavage. Safe in ultrasonic cleaners. | Fair to good. Softer than topaz, prone to chipping. Sensitive to heat and sudden temperature changes. Avoid ultrasonic cleaners. | Poor to fair. Softer and porous. Susceptible to scratching, cracking, and discoloration from chemicals, lotions, and water. Requires gentle cleaning with a soft, dry cloth. |
Blue Topaz is the hardest of the three, with a Mohs hardness of 8, making it an excellent choice for rings and daily wear jewelry. Its vitreous luster and good clarity allow for brilliant faceted cuts that maximize its blue color. However, it can have natural inclusions and is often treated to enhance its color.
Tanzanite has a hardness of 6.5 to 7, which is adequate for jewelry but requires more care than topaz. It is known for its strong trichroism, displaying three different colors—blue, violet, and redish-purple—depending on the viewing angle. This property is carefully considered during cutting to present the most desirable blue-violet hue. Tanzanite is also pleochroic, meaning its color intensity can change with light source.
Turquoise is the softest and most porous of the three, with a hardness of 5 to 6. It is typically cut en cabochon (a smooth, rounded dome) rather than faceted, as this shape best showcases its unique color and often intricate matrix patterns. Its waxy luster and opaque nature are hallmarks of the stone. Due to its porosity, Turquoise can absorb oils and chemicals, which may alter its color over time.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, these gemstones are deeply embedded in cultural symbolism and metaphysical traditions, each offering a unique set of meanings to the wearer.
Blue Topaz is widely associated with communication, wisdom, and serenity. Its clear, tranquil blue color is believed to calm the mind, reduce stress, and promote honest, clear expression. In metaphysical circles, it is often linked to the Throat Chakra, aiding in truthful communication and self-expression. It is also thought to bring a sense of peace and relaxation, making it a popular stone for those seeking emotional balance and mental clarity.
Tanzanite, as a relatively new discovery, has quickly developed a strong metaphysical reputation. It is celebrated for its connection to spiritual growth and transformation. Its unique, multi-colored energy is believed to activate the higher mind, facilitating a deeper connection to one's intuition and spiritual purpose. Many consider it a stone of metamorphosis, helping the wearer navigate significant life changes and awaken to new possibilities. Its rarity is often linked to the idea of seizing a unique, once-in-a-lifetime opportunity.
Turquoise is one of the most powerful protective stones in gem lore. For centuries, it has been regarded as a talisman for protection, good fortune, and healing. It is believed to shield the wearer from negative energy, accidents, and ill will. Many cultures, particularly Native American tribes, view Turquoise as a sacred stone that connects the physical and spiritual worlds, promoting inner peace and emotional grounding. It is also associated with prosperity and luck, making it a common gift for travelers and those embarking on new ventures.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of any gemstone jewelry. The distinct properties of Blue Topaz, Tanzanite, and Turquoise dictate specific maintenance protocols.
Blue Topaz, with its high hardness, is relatively easy to care for. It can be cleaned with warm water, mild soap, and a soft brush. It is generally safe in an ultrasonic cleaner, but caution is advised if the stone has fractures or inclusions. As with all fine jewelry, it should be stored separately to avoid scratches from harder gems.
Tanzanite requires more careful handling due to its lower hardness and potential for cleavage. Clean it with a soft, damp cloth and avoid harsh chemicals, extreme temperatures, and ultrasonic cleaners, which can cause damage. It is best to remove Tanzanite rings before engaging in activities that could lead to impact or abrasion.
Turquoise demands the most diligent care. It should be cleaned only with a soft, dry cloth; water and commercial jewelry cleaners can penetrate its porous structure, leading to discoloration or damage. To preserve its color, avoid exposing Turquoise to lotions, perfumes, oils, and prolonged sunlight. It is advisable to wipe the stone with a soft cloth after wear to remove any skin oils. Storing it in a soft pouch will protect it from scratches and environmental factors.
The choice of a December birthstone ring, whether it features the serene Blue Topaz, the transformative Tanzanite, or the protective Turquoise, is a personal journey. Each stone offers a unique blend of color, history, and meaning, allowing for a deeply personal connection to the month of December. With proper understanding and care, a December birthstone ring can be a cherished piece of jewelry for a lifetime.
Conclusion
The December birthstones—Blue Topaz, Tanzanite, and Turquoise—represent a remarkable convergence of geological wonder, historical significance, and personal symbolism. From the ancient, protective talismans of Turquoise to the recently discovered, spiritually awakening Tanzanite, and the clear, communicative Blue Topaz, each gemstone provides a distinct voice for the December-born. Their varying gemological properties, from the durable hardness of Topaz to the delicate nature of Turquoise, inform not only their use in jewelry but also the care required to preserve their beauty. As both objects of scientific fascination and carriers of deep cultural meaning, these three gemstones continue to captivate collectors, jewelers, and enthusiasts, ensuring their place as timeless symbols of the month of December.