December, the final month of the year, is uniquely distinguished by its association with not one, but four officially recognized birthstones. Among all months, it holds the most diverse selection of gemstones—Turquoise, Tanzanite, Blue Topaz, and Zircon—each with its own rich history, captivating color palette, and distinct gemological properties. These gems reflect the cool, tranquil tones of winter and offer a fascinating blend of ancient tradition, modern discovery, and practical value in the jewelry industry. This article delves into the origins, characteristics, symbolism, and care of each of these December birthstones, offering a comprehensive overview grounded in gemological and historical insights.
Introduction
December is a month of transition—marking the end of one year and the beginning of another. Its birthstones mirror this duality, combining ancient lore with modern appreciation. The tradition of associating gemstones with specific months is believed to have originated in Mesopotamia and later been adopted by the Greeks and Romans. Over time, the list of December birthstones has expanded from just two to four, reflecting both cultural shifts and the discovery of new gemstones.
Each December birthstone possesses a unique blue or blue-related hue—ranging from the soft, sky-blue tones of turquoise and blue topaz to the deep violet of tanzanite and the vibrant brilliance of zircon. These gems are not only visually striking but also carry a range of symbolic meanings and historical significance. Whether chosen for personal adornment, jewelry design, or as a meaningful gift, these stones offer a rich tapestry of beauty and meaning.
The following sections explore each December birthstone in detail, covering their geological origins, historical uses, gemological properties, and cultural symbolism. Practical information on care and cleaning is also included, ensuring that these gems can be enjoyed and preserved for generations.
History and Lore
Ancient Roots of the December Birthstones
The use of gemstones for personal adornment and symbolic purposes dates back thousands of years. While the concept of associating specific stones with the months of the year has evolved over time, some of December’s birthstones have ancient roots.
Turquoise, for example, has been revered for millennia. The ancient Egyptians used it in amulets and jewelry, believing it to bring protection and good fortune. It was also used by Native American tribes, who valued it for its spiritual properties and used it in rituals and ceremonies. The word “turquoise” itself is derived from the French pierre turquoise, meaning “Turkish stone,” as the gem was historically brought to Europe via Turkey.
Zircon, on the other hand, has a more elusive history. It is one of the oldest minerals on Earth, with some zircons dating back over 4 billion years. The stone was used in ancient jewelry in Asia and the Middle East, and its name is believed to derive from the Arabic word zir, meaning "moonstone." Zircon was also known in the Middle Ages, but it was not until the 20th century that it was officially recognized as a December birthstone.
Modern Expansion of the December Birthstone List
The modern list of December birthstones was formalized in the 20th century, reflecting the changing landscape of gemology and the jewelry industry. In 1912, the National Association of Jewelers standardized the list of American birthstones, incorporating both traditional and newly discovered gems. This process continued in 1952 with the addition of zircon to the list, and in 2002, tanzanite was added.
Tanzanite is a particularly interesting addition to the list, as it is a relatively modern discovery. First identified in 1967 in Tanzania, it was marketed as a luxury gemstone and quickly gained popularity. Its deep blue-violet color and rarity made it a natural fit for the December birthstone collection, and it was officially added in 2002 by the American Gem Trade Association (AGTA).
The inclusion of multiple birthstones for December—especially the addition of blue topaz—also reflects a practical consideration. As one of the hardest of the December birthstones, blue topaz is well-suited for everyday wear and offers a more affordable option for jewelry buyers.
Geological Formation and Sources
Each of December’s birthstones is formed under unique geological conditions and is found in specific regions around the world.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper. It forms in arid regions where copper-rich veins are exposed to weathering, leading to the formation of the characteristic blue or greenish-blue mineral. The most well-known sources of turquoise include:
- Iran (Persia) – Historically the most important source of high-quality turquoise.
- United States – Arizona, Nevada, and New Mexico are major producers of turquoise in North America.
- China, Egypt, and Mexico – Also known for producing turquoise in various colors and qualities.
The quality of turquoise varies depending on its hardness, porosity, and the presence of matrix (the dark veins that run through the stone). High-quality turquoise is typically hard, smooth, and free of large amounts of matrix.
Tanzanite
Tanzanite is a form of zoisite, a calcium aluminum silicate. It is unique in that it was discovered in 1967 in the Merelani Hills of Tanzania, near Mount Kilimanjaro. Tanzanite forms in metamorphic rock and is prized for its trichroism—meaning it displays three different colors (blue, violet, and brown) depending on the viewing angle.
Due to its limited geographic origin and the fact that mining is restricted to a small area, tanzanite is considered one of the rarest gemstones in the world. The mine has a finite supply, and it is estimated that it will be depleted within the next few decades.
Blue Topaz
Blue topaz is a form of topaz that has been treated to enhance its natural color. While topaz can occur in a wide range of colors, including colorless, yellow, and brown, the blue color is the most popular and is achieved through irradiation and heat treatment.
Natural blue topaz is extremely rare, so the majority of blue topaz on the market is treated. The treatment does not affect the gem’s durability or value but allows for a more consistent and desirable color. Blue topaz is mined in several countries, including:
- Brazil
- Nigeria
- Sri Lanka
- United States (especially in Texas, where it is the state gem)
Zircon
Zircon is a silicate mineral that occurs in a wide range of colors, including colorless, yellow, red, and blue. The blue zircon used in jewelry is typically heat-treated to achieve its vivid blue color. Zircon is found in many parts of the world, including:
- Australia
- Sri Lanka
- Thailand
- Madagascar
- Brazil
Zircon is known for its high refractive index, which gives it a brilliant, fiery appearance. It is also relatively durable, with a hardness of 6.5 to 7.5 on the Mohs scale, making it suitable for everyday wear in well-made jewelry.
Gemological Properties
| Gemstone | Color | Hardness (Mohs) | Chemical Formula | Origin | Treatments Commonly Used |
|---|---|---|---|---|---|
| Turquoise | Blue, greenish-blue | 5–6 | Al₂(OH)₃PO₄ | Iran, U.S., China, Egypt | Stabilization, dyeing |
| Tanzanite | Blue, violet | 6–7 | Ca₂Al₃(SiO₄)₃(OH) | Tanzania | Heat treatment |
| Blue Topaz | Blue | 8 | Al₂SiO₆ | Brazil, U.S., Nigeria, Sri Lanka | Irradiation, heat treatment |
| Zircon | Blue, colorless, yellow, red | 6.5–7.5 | ZrSiO₄ | Australia, Thailand, Brazil | Heat treatment |
Turquoise
Turquoise has a hardness of 5 to 6 on the Mohs scale, making it relatively soft compared to other gemstones. This softness means that it requires careful handling and is best suited for pieces that are not subject to daily wear, such as pendants or earrings. Its color can vary from a pale blue to a deep greenish-blue, depending on the concentration of copper and the presence of iron.
Tanzanite
Tanzanite has a hardness of 6 to 7, making it more durable than turquoise but still not as tough as topaz. It is also trichroic, meaning it can display three different colors when viewed from different angles. Tanzanite is usually heat-treated to enhance its blue and violet tones, which are considered the most desirable.
Blue Topaz
Blue topaz is one of the hardest December birthstones, with a hardness of 8 on the Mohs scale. This makes it ideal for everyday wear and suitable for engagement rings and other fine jewelry. Most blue topaz is treated with irradiation and heat to achieve its intense blue color, a process that is stable and does not affect the gem's durability.
Zircon
Zircon has a hardness of 6.5 to 7.5, making it relatively durable and suitable for use in rings and other jewelry. It is known for its high refractive index, which gives it a brilliant, fiery sparkle. Blue zircon is the most popular color for jewelry and is usually heat-treated to achieve this color.
Symbolism and Metaphysical Beliefs
Each of December’s birthstones carries its own set of symbolic meanings and metaphysical properties, many of which have been passed down through generations.
Turquoise
Turquoise has long been associated with protection, healing, and good fortune. It is believed to promote emotional balance and calmness, making it a popular stone for those seeking grounding and inner peace. In many cultures, it is also associated with spiritual guidance and communication with higher powers.
Tanzanite
Tanzanite is often linked to transformation, intuition, and spiritual growth. Its deep blue-violet color is said to enhance emotional healing and encourage open-hearted communication. It is also believed to help individuals embrace new opportunities and navigate change with confidence.
Blue Topaz
Blue topaz is associated with serenity, wisdom, and clarity. It is believed to help reduce stress and promote a sense of calm and optimism. It is also thought to enhance creativity and encourage self-expression.
Zircon
Zircon is often associated with wisdom, clarity, and spiritual insight. It is believed to help sharpen the mind, improve focus, and enhance one’s ability to see the truth in situations. Zircon is also considered a stone of protection, especially against negative energies.
Care and Cleaning
Each of December’s birthstones requires specific care to maintain its beauty and durability.
Turquoise
Due to its softness and porosity, turquoise should be handled with care. It should not be exposed to harsh chemicals, prolonged sunlight, or excessive moisture, as this can cause it to fade or crack. Clean it gently with a soft cloth and warm, soapy water. Avoid ultrasonic or steam cleaning.
Tanzanite
Tanzanite is more durable than turquoise but still requires careful handling. Avoid exposure to extreme heat or chemicals. Clean it with a soft cloth and warm, soapy water. Avoid using harsh abrasives or ultrasonic cleaners.
Blue Topaz
Blue topaz is one of the most durable of the December birthstones and can be cleaned with standard jewelry cleaning methods. It can be cleaned with warm, soapy water, a soft brush, and a polishing cloth. It is also safe to use ultrasonic and steam cleaners.
Zircon
Zircon is relatively durable but should still be handled with care to avoid chipping. Clean it with warm, soapy water and a soft brush. Avoid harsh chemicals and high heat, as these can damage the gem.
Conclusion
December’s birthstones—Turquoise, Tanzanite, Blue Topaz, and Zircon—offer a remarkable blend of beauty, history, and symbolism. Each gemstone reflects the cool tones of winter and carries its own unique story, from ancient traditions to modern discoveries. Whether chosen for their gemological properties, symbolic meanings, or aesthetic appeal, these stones provide a rich and meaningful connection to the month of December.
For those born in December, these gems serve as a powerful representation of their birth month, offering not only visual beauty but also a sense of personal identity and meaning. Whether used in jewelry, worn as a talisman, or simply admired for their natural elegance, these December birthstones continue to captivate gemstone enthusiasts and jewelry lovers alike.