In the world of gemstones, few months offer the diverse and captivating palette of December. While some months are anchored by a single stone, December boasts three distinct birthstones: the serene blue of Topaz, the vibrant violet-blue of Tanzanite, and the ancient turquoise. Each carries its own unique history, geological origin, and symbolic meaning, providing a rich spectrum of choices for those born in the final month of the year. This article explores the gemological properties, cultural significance, and practical considerations of these three remarkable stones, offering a comprehensive guide for collectors, enthusiasts, and anyone drawn to their timeless allure.
The Modern Trio of December
The contemporary list of birthstones, largely standardized by the American National Retail Jewelers Association in 1912 and periodically updated, recognizes Blue Topaz, Tanzanite, and Turquoise as the primary stones for December. This selection reflects a blend of historical tradition and modern market availability. Blue Topaz, with its cool, sky-blue hue, offers clarity and affordability. Tanzanite, a relative newcomer to the gem world, brings a unique violet-blue coloration found in only one location on Earth. Turquoise, one of the oldest gemstones in human history, provides a connection to ancient cultures and protective symbolism. Together, they give December-born individuals a range of options, from the ethereal to the earthy, each with its own story.
History and Lore
Blue Topaz: The Stone of Serenity
While topaz has been known since antiquity, the specific blue variety has a more recent history in the birthstone canon. Historically, the term "topaz" was often used for a range of yellow and golden stones. The association of blue topaz with December is a modern development, gaining prominence in the 20th century as treatments made its desirable blue color more widely available. According to gemological lore, blue topaz is linked to communication, wisdom, and serenity. Its calm, clear blue is said to promote peacefulness and mental clarity, making it a stone for those seeking tranquility and honest expression.
Tanzanite: A Rare Discovery
Tanzanite's history is remarkably brief. Discovered in the late 1960s in the Merelani Hills of Tanzania, this gemstone was introduced to the global market by Tiffany & Co. in 1968, who named it for its country of origin. Its rapid rise to prominence led to its adoption as a December birthstone in 2002. Geologically, it is a variety of the mineral zoisite, and its unique violet-blue color is the result of heat treatment, which is standard for nearly all commercial tanzanite. Culturally, tanzanite is often associated with spiritual growth, transformation, and a connection to higher consciousness. Its rarity and the fact that its source is confined to a small area in Tanzania add to its mystique and value.
Turquoise: An Ancient Protector
Turquoise is arguably the most historically significant of the three December stones. Evidence of its use dates back over 5,000 years, with artifacts found in ancient Egyptian tombs and among Persian and Native American cultures. The name "turquoise" itself derives from the French "pierre tourquoise," meaning "Turkish stone," referencing the trade routes that brought the gem to Europe from Persia (modern-day Iran). For centuries, it has been revered as a talisman of protection, good fortune, and healing. In many cultures, it is believed to ward off negative energy and bring peace to the wearer. Its status as a December birthstone is deeply rooted in this long-standing tradition, making it a stone rich with cultural heritage.
Geological Formation and Sources
Blue Topaz
Topaz is a silicate mineral that forms in pegmatites, which are igneous rocks with very large crystals, and in high-temperature hydrothermal veins. While natural blue topaz does occur, the intense, even blue color seen in most commercial jewelry is achieved through irradiation and heat treatment of colorless or pale yellow topaz. The primary sources of topaz include Brazil, Sri Lanka, Nigeria, and the United States (specifically Texas and California). The treatment process is stable and permanent, and the resulting blue topaz is a durable and affordable gemstone.
Tanzanite
Tanzanite is a variety of zoisite that forms under specific geological conditions. It is found exclusively in the Merelani Hills of northern Tanzania, near the base of Mount Kilimanjaro. The formation of tanzanite is linked to the tectonic activity in the East African Rift, which created the unique conditions necessary for its crystallization. This geographic restriction makes it one of the rarest gemstones in the world. The vast majority of tanzanite on the market has been heat-treated to enhance its color from a brownish or greenish hue to the prized violet-blue.
Turquoise
Turquoise is a phosphate mineral that forms in arid regions where acidic water percolates through rocks rich in copper, aluminum, and phosphorus. This process creates nodules or veins of turquoise in host rocks. Major sources include the United States (especially Arizona, New Mexico, and Nevada), Iran, China, and Egypt. The color of turquoise is influenced by the presence of copper (which creates blue) and iron or zinc (which can create green tones). The stone is often found in matrix, a host rock that can create unique patterns, such as the famous spiderweb patterns of some Persian turquoise.
Gemological Properties
The three December stones differ significantly in their physical and chemical properties, which influence their durability, care, and use in jewelry.
| Property | Blue Topaz | Tanzanite | Turquoise |
|---|---|---|---|
| Mineral Family | Silicate (Nesosilicate) | Silicate (Sorosilicate - Zoisite) | Phosphate (Hydrated copper aluminum phosphate) |
| Chemical Formula | Al₂SiO₄(F,OH)₂ | Ca₂Al₃(SiO₄)₃(OH) | CuAl₆(PO₄)₄(OH)₈·4H₂O |
| Hardness (Mohs) | 8 | 6.5 - 7 | 5 - 6 |
| Crystal System | Orthorhombic | Orthorhombic | Triclinic |
| 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 |
| Typical Treatments | Irradiation, Heat (for color) | Heat (standard) | Stabilization (common) |
| Color Range | Light to deep blue | Violet-blue to pure blue | Sky blue to greenish blue |
Blue Topaz is the hardest of the three, scoring an 8 on the Mohs scale of mineral hardness. This makes it highly resistant to scratching and suitable for everyday wear in rings and bracelets. Its chemical composition is aluminum silicate with fluorine or hydroxyl groups.
Tanzanite has a hardness of 6.5 to 7, which is moderate. While durable enough for most jewelry, it can be susceptible to chipping or cracking if struck hard, making it more suitable for earrings, pendants, and occasional-wear rings rather than daily-wear rings. It is a member of the epidote group and is composed of calcium aluminum silicate.
Turquoise is the softest of the three, with a hardness of 5 to 6. This makes it prone to scratching and abrasion. It is also porous and can be affected by chemicals, cosmetics, and even skin acids. For this reason, most commercial turquoise is stabilized—a process where the stone is impregnated with a clear resin to harden it and improve its color stability. Its chemical formula is a hydrated copper aluminum phosphate, and its color is directly linked to the copper content.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, the December birthstones are steeped in symbolic meaning and metaphysical lore.
Blue Topaz is widely regarded as a stone of clarity, peace, and communication. It is believed to calm tempers, soothe fears, and promote honest expression. In metaphysical circles, it is associated with the Throat Chakra, enhancing verbal communication and self-expression. Its serene blue color is linked to emotional balance and mental clarity.
Tanzanite, due to its unique color and recent discovery, is often called the "stone of transformation." It is said to facilitate spiritual awakening, psychic abilities, and a connection to higher consciousness. Its energy is described as both calming and stimulating, helping to bridge the gap between the physical and spiritual realms. It is also associated with the Crown and Throat Chakras.
Turquoise is one of the most powerful protection stones. It is believed to absorb negative energy and provide a shield against harm. Historically, it was worn by warriors and travelers for safety. It is also associated with good fortune, healing, and emotional balance. Many cultures believe it can connect the wearer to the natural world and bring peace of mind.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of these gemstones, given their varying properties.
Blue Topaz: Due to its high hardness and stability, blue topaz is relatively easy to care for. It can be cleaned with warm water, mild soap, and a soft brush. Ultrasonic and steam cleaners are generally safe, but it is always advisable to check with a professional jeweler, especially if the stone is set in a delicate or complex setting.
Tanzanite: With a moderate hardness, tanzanite requires gentle handling. It should be cleaned with warm, soapy water and a soft cloth. Avoid ultrasonic cleaners and steam, as the vibrations and heat can potentially cause damage or fracture the stone, especially if there are existing inclusions. It is best to remove tanzanite jewelry before engaging in activities where it might be struck.
Turquoise: Turquoise is the most delicate and requires the most care. It should never be exposed to chemicals, cosmetics, perfumes, or even prolonged contact with skin oils, as these can cause discoloration or damage the stone's surface. Clean it only with a soft, dry cloth. Avoid water, as untreated turquoise can absorb it, leading to potential damage or changes in appearance. Stabilized turquoise is more resistant but still requires gentle handling. Store it separately from harder stones to prevent scratching.
Conclusion
The December birthstones—Blue Topaz, Tanzanite, and Turquoise—offer a remarkable range of options that cater to diverse tastes and preferences. Blue Topaz provides clarity and durability with its serene blue hue, while Tanzanite offers a rare, vibrant color associated with transformation. Turquoise connects the wearer to ancient traditions and provides a sense of protection and grounding. Each stone, from its geological formation to its cultural significance, tells a unique story. For those born in December, the choice of birthstone is a personal journey, selecting a gem that not only captures the eye but also resonates with their individual spirit. Whether chosen for its beauty, its history, or its symbolic meaning, any of these three stones makes a timeless and meaningful addition to any jewelry collection.