December is unique among the months for having not one, but three traditional birthstones: turquoise, tanzanite, and zircon. This trio offers a remarkable spectrum of blue hues, from the soft, sky-blue of turquoise to the vivid, violet-blue of tanzanite and the brilliant, clear blue of zircon. This abundance provides individuals born in December with a wealth of choice, allowing them to select a gemstone that resonates with their personal style, budget, and the meanings they wish to embody. Each stone carries its own distinct history, geological origin, and set of gemological properties, making the study of these December birthstones a fascinating journey through geology, history, and culture.
The association of these gems with December is a relatively modern development, primarily stemming from the 1912 standardization by the National Association of Jewelers in the United States, which was based on older historical and biblical traditions. While turquoise has been cherished for millennia, tanzanite is a discovery of the 20th century, and zircon has a long history often confused with the synthetic cubic zirconia. This article will delve into the individual stories of these three remarkable gems, exploring their unique characteristics, the lore surrounding them, and the practical considerations for those who wear them.
Turquoise: The Ancient Stone of the Sky
History and Lore
Turquoise is arguably the most ancient of the December birthstones, with a history that stretches back thousands of years. Its name is derived from the French phrase pierre turquoise, meaning "stone of Turkey," as it was brought to Europe from Turkish bazaars. However, its origins lie elsewhere. The gem was found in Persia (modern-day Iran) and along the Sinai Peninsula and was transported to Europe through the gem markets of Constantinople, Turkey.
This gemstone has been a favorite for amulets and protective talismans since antiquity. Its relative softness made it easy to cut into various shapes and to inscribe upon. Across cultures, it was believed to possess protective powers, warding off danger and bringing good fortune. In many traditions, it was a stone of love and fidelity, prized by lovers and married couples for its ability to preserve relationships and friendships when given as a gift. A particularly widespread belief was that turquoise could warn its wearer of impending illness or danger by changing color, often becoming pale.
The stone's significance is deeply embedded in numerous cultures. Tibetan culture considered turquoise a birthstone of fortune, health, and success, and it was so valued that it was often used as a form of currency. In the Americas, Native American tribes of the Southwest associated it with youth and strength. The Apache believed one could find turquoise by following a rainbow to its end. For the ancient Incas and Mayas, it was an offering to the gods. In ancient Egypt, pharaohs and other rulers adorned themselves with it, and Chinese artisans were carving it more than 3,000 years ago.
Geological Formation and Sources
Turquoise is a hydrous phosphate of copper and aluminum. It is formed when groundwater containing copper seeps into bedrock, reacting with other minerals over long periods to create an opaque stone. The stunning range of blues and greens is directly influenced by the copper content (blue) and iron (green). The dark lines and shapes visible within many turquoise stones are fragments of the surrounding rock, known as matrix, which become part of the gem as it forms.
Historically, significant sources include Persia (Iran), the Sinai Peninsula, and the southwestern United States. The specific location of origin can influence the stone's color and matrix patterns, which are key identifiers for gemologists and collectors.
Gemological Properties
Turquoise is a semi-translucent to opaque gem. Its color ranges from soft sky blue to greenish hues, often with a distinctive matrix. On the Mohs scale of hardness, it ranks between 5 and 6, making it relatively soft and susceptible to scratching. This lower hardness requires careful handling and cleaning. It has a waxy to dull luster, which can be enhanced by polishing. Due to its porosity and softness, turquoise is often stabilized or treated with wax or resin to improve its durability and color, a common and accepted practice in the gem trade.
Symbolism and Metaphysical Beliefs
The symbolism of turquoise is overwhelmingly positive and protective. It is linked to good fortune, health, and success. Its calming blue-green color is often associated with tranquility, grounding, and emotional balance. Many believe it acts as a steadying force, offering protection and a sense of calm during chaotic times. In modern metaphysical beliefs, it is considered a stone of communication and creativity, helping to align the chakras and foster a sense of spiritual grounding.
Care and Cleaning
Due to its softness and porosity, turquoise requires special care. It should not be exposed to harsh chemicals, including household cleaners, cosmetics, and perfumes, which can damage its surface. Cleaning should be done with a soft, damp cloth and mild soap, avoiding ultrasonic and steam cleaners. It is best to store turquoise jewelry separately to prevent scratching by harder gems. Prolonged exposure to heat or strong sunlight can cause fading or drying, so it should be kept in a cool, dark place when not worn.
Tanzanite: The Gem of a Single Source
History and Lore
Tanzanite is the newest of the December birthstones, a 20th-century discovery that quickly captured the imagination of the gem world. It was first found in 1967 in the Merelani Hills of northern Tanzania, near the base of Mount Kilimanjaro. Its discovery is attributed to a local Maasai tribesman, Ali Juuyawatu, who brought the blue crystals to the attention of a gem dealer. The gem was later named "tanzanite" by Tiffany & Co. in honor of its country of origin, and the company launched a major marketing campaign in 1968 that propelled it to international fame.
Because it is found in only one location on Earth, tanzanite is considered a "gemological phenomenon." Its rapid rise to prominence is a testament to its extraordinary beauty. The gem's lore is inherently modern, often linked to themes of transformation, new beginnings, and heightened awareness. Its unique blue-violet hue is seen as a reflection of stepping into a new chapter of life with clarity and curiosity.
Geological Formation and Sources
Tanzanite's formation is a geological rarity. It is a variety of the mineral zoisite, and its blue-to-violet color is the result of heat treatment of brownish zoisite crystals. This heating process, which occurs naturally in the earth or is replicated in labs, is permanent and is a standard, disclosed practice in the gem trade. The primary and currently only significant source for tanzanite is a small mining area in the Merelani Hills of Tanzania. This limited geographic source makes the gem particularly precious and raises concerns about its long-term availability.
Gemological Properties
Tanzanite is prized for its rich, pleochroic color, which can display shades of blue, violet, and burgundy depending on the crystal orientation and lighting. It is a relatively soft gem, ranking 6 to 7 on the Mohs scale, making it less durable than sapphire or diamond. It has a vitreous luster and is typically found in larger, cleaner crystals than many other gems, allowing for impressive faceted cuts. Its most distinctive feature is its strong trichroism, showing three different colors in different directions: blue, violet, and red-violet.
Symbolism and Metaphysical Beliefs
Tanzanite is associated with transformation, intuition, and spiritual awakening. Its striking color is believed to stimulate the throat and third-eye chakras, enhancing communication and psychic abilities. It is often called the "stone of magic" for its ability to facilitate a connection between the mind and the heart. In modern crystal healing, it is used to promote calmness, relieve stress, and support major life changes. Its symbolism is deeply tied to its origin story—a gem born from a unique geological event, much like a personal breakthrough.
Care and Cleaning
Tanzanite's relative softness and perfect cleavage in one direction make it vulnerable to damage. It should be protected from sharp blows and rough handling. It is not recommended for everyday rings, especially for those with an active lifestyle. Cleaning should be done with warm, soapy water and a soft brush, avoiding ultrasonic cleaners and steam, which can cause fractures. It should be stored carefully to avoid contact with harder gems.
Zircon: The Sparkling Misunderstood Gem
History and Lore
Zircon has a long and storied history, though it is often confused with the synthetic material cubic zirconia (CZ). Natural zircon is one of the oldest minerals on Earth, with some crystals dating back billions of years. For centuries, it was used as a protective talisman and was believed to aid in sleep, promote prosperity, and foster honor. In the Middle Ages, it was thought to drive away evil spirits and encourage a sound night's sleep. Its name is derived from the Persian word zargun, meaning "gold-colored," though the most prized variety today is the brilliant blue.
The blue variety of zircon became particularly popular in the Victorian era for its diamond-like brilliance and fire. Its association with wisdom, clarity, and balance is a more modern interpretation, linking its clear, bright appearance to mental acuity and emotional equilibrium.
Geological Formation and Sources
Zircon is a zirconium silicate (ZrSiO₄) and is a common accessory mineral in many igneous and metamorphic rocks. It forms under high-temperature conditions and is highly resistant to weathering, which is why it is often found in sedimentary deposits. The blue color in most commercial blue zircon is achieved through heat treatment of brownish zircon crystals. This treatment is permanent and is a standard industry practice. Significant sources of zircon include Cambodia, Myanmar, Sri Lanka, and Australia. The stone's brilliance is due to its high refractive index, which is close to that of diamond.
Gemological Properties
Zircon is one of the hardest gemstones among the December trio, ranking 6.5 to 7.5 on the Mohs scale, making it more durable than turquoise and tanzanite for certain types of jewelry. It possesses a high refractive index (1.92-2.01) and strong dispersion (0.039), giving it exceptional brilliance and fire, often compared to that of a diamond. It is typically found in smaller sizes due to its crystal habit and the cost of cutting. Its color ranges from clear to blue, yellow, green, and red, with blue being the most popular for December birthstone jewelry. Zircon is also radioactive in some varieties, which can cause crystal metamictization over time, but this is not a concern for commercially available gemstones.
Symbolism and Metaphysical Beliefs
Zircon is symbolically linked to clarity, wisdom, and balance. Its brilliant sparkle is thought to enhance mental focus and bring emotional stability. In metaphysical practices, it is believed to support spiritual growth, provide protection during travel, and attract prosperity and honor. It is also associated with restful sleep and the alleviation of nightmares, echoing its historical use as a protective talisman.
Care and Cleaning
While zircon is relatively hard, it can be brittle due to its perfect cleavage in one direction. It is susceptible to chipping if struck with force. It should be protected from sharp impacts. Cleaning is straightforward: use warm, soapy water and a soft brush. Avoid ultrasonic cleaners and sudden temperature changes, which can cause fractures. It is best to store zircon jewelry separately in a soft cloth or padded box.
Comparative Analysis and Selection
Choosing among the three December birthstones involves weighing their unique attributes against personal preferences and practical considerations.
| Gemstone | Color Range | Hardness (Mohs) | Durability | Key Symbolism | Primary Source |
|---|---|---|---|---|---|
| Turquoise | Soft sky blue to greenish hues, often with matrix | 5 - 6 | Fair (soft, porous) | Protection, good fortune, calm | Iran, USA, China |
| Tanzanite | Rich violet-blue to blue, strong pleochroism | 6 - 7 | Fair (soft, perfect cleavage) | Transformation, intuition, new beginnings | Tanzania (only) |
| Zircon | Bright, clear blue (treated); also colorless, yellow | 6.5 - 7.5 | Good (brittle, perfect cleavage) | Clarity, wisdom, balance | Cambodia, Myanmar, Sri Lanka |
For the Collector of History: Turquoise is unparalleled, with a lineage stretching back to ancient Egypt, Persia, and the Americas. Its cultural narratives are rich and deeply varied.
For the Seeker of Rarity: Tanzanite is the ultimate choice. Its existence is confined to a single, small mining area, making each stone a piece of a unique geological story.
For the Lover of Brilliance: Zircon offers the most diamond-like sparkle among the three. Its high refractive index and dispersion create a fiery, lively gem that is particularly striking in well-cut pieces.
For Everyday Wear: Zircon, with a hardness of up to 7.5, is the most durable option for rings that will see daily activity, provided it is set in a protective setting. Tanzanite and turquoise are better suited for pendants, earrings, and occasional-wear rings.
Conclusion
The December birthstones—turquoise, tanzanite, and zircon—offer a remarkable diversity within the blue gemstone family. From the ancient, protective talisman of turquoise to the modern, transformative allure of tanzanite and the brilliant, clear fire of zircon, each gem provides a distinct narrative and aesthetic. Their selection is not merely a matter of color preference but a choice that connects the wearer to specific histories, geological wonders, and symbolic meanings. Understanding their individual properties, from hardness and cleavage to cultural lore, allows for an informed and meaningful selection, ensuring that a December birthstone remains a cherished possession for years to come.