December is uniquely distinguished in the world of gemstones, offering not one, but four official birthstones. This remarkable variety sets it apart from most other months, providing individuals born in the final month of the year with a diverse palette of colors, histories, and symbolic meanings to choose from. The primary birthstones for December are Turquoise, Zircon, Tanzanite, and Blue Topaz. These gems collectively capture the icy, enchanting charm of winter, with their cool blues and greens evoking the serene landscapes of the season. Unlike a single-stone month, December’s birthstones allow for personal expression, whether one is drawn to the ancient protective talisman of turquoise, the brilliant fire of zircon, the transformative energy of tanzanite, or the tranquil clarity of blue topaz.
This article delves into the rich tapestry of December’s birthstones, exploring their geological origins, gemological properties, historical significance, and the symbolism that has made them cherished across cultures and centuries. From the sun-baked deserts where turquoise forms to the volcanic rifts of East Africa where tanzanite was discovered, each stone tells a unique story. We will examine the official status of these gems, their journey to becoming modern birthstones, and the practical considerations for their care, providing a comprehensive guide for gemstone enthusiasts, jewelry buyers, and students of gemology.
History and Lore: From Ancient Talismans to Modern Lists
The history of December’s birthstones is as varied as the stones themselves, tracing back through ancient calendars, religious texts, and evolving trade practices. The modern concept of birthstones, however, was formalized in the early 20th century. The American National Retail Jeweler's Association (now Jewelers of America) established the first official list in 1912, which has been updated periodically to reflect new discoveries and market trends. According to sources, the primary December birthstone is Turquoise, with Tanzanite and Zircon also officially recognized by major gemological bodies like the Gemological Institute of America (GIA). Blue Topaz is frequently included in lists from organizations such as the American Gem Society, further cementing its place as a popular December choice.
Turquoise holds the title of the oldest December birthstone, with a history spanning over 3,000 years. It was cherished by ancient civilizations, including the Egyptians, who were buried with it for protection in the afterlife. Its use as a protective talisman against falls and negative energy is a consistent theme throughout its lore. In the Gregorian birthstone poem, it is famously celebrated: "If cold December gave you birth, / The month of snow and ice and mirth, / Place on your hand a turquoise blue; / Success will bless whate’er you do." This poetic connection underscores its enduring status as a symbol of good luck and wisdom.
Zircon also has a deep historical pedigree as a traditional birthstone for December. It is notably listed as a traditional birthstone alongside Ruby and Lapis Lazuli. In 1952, zircon replaced Lapis Lazuli in the U.S. modern birthstone list, a change that highlights the evolving nature of these designations. Its brilliance and fire have made it a prized gem for centuries, though its history is sometimes overshadowed by its more common cousin, cubic zirconia.
Tanzanite is the newest addition to the December family, earning its place in 2002 through the American Gem Trade Association. Its inclusion was a strategic move to highlight a rare gem and expand options for December-born individuals. Discovered in the foothills of Mount Kilimanjaro in Tanzania, East Africa, in the mid-20th century, tanzanite is geologically one of a kind, found only in this specific region. Its rapid rise to birthstone status is a modern gemological success story.
Blue Topaz, while not always listed on the earliest official charts, has become a staple in modern jewelry. Its designation as a December birthstone specifically refers to the blue variety of this silicate mineral. Sources indicate that topaz is the birthstone for December in the Hindu calendar, and in the West, it is the blue variety that is specifically designated as the December stone. Its journey from a colorless gem to a vibrant blue birthstone involves a process of treatment, which we will explore in the gemological properties section.
Beyond these four, historical and cultural lists reveal a wider array of stones associated with December. For instance, Bloodstone (heliotrope) is a traditional birthstone for December from as far back as the 15th century. This green chalcedony with red inclusions was believed to enhance courage and physical strength. Ruby, the red variety of corundum, was the ancient birthstone for December in the old Arabic, Hebrew, Italian, Roman, and Indian (Ayurvedic) calendars. It was also the zodiac stone for Capricorn, which falls partly in December, and is believed to strengthen the mind and bestow courage. Other stones like Chrysoprase (an apple-green chalcedony from the old Russian calendar), Onyx (a black and white banded chalcedony from the old Tibetan calendar), and Cat's Eye (from the Indian calendar) also appear in historical records. The December birthstone color is predominantly blue, as seen in turquoise, tanzanite, blue topaz, and lapis lazuli, but non-conventional stones like ruby (red), onyx (black), and chrysoprase (green) add to the color spectrum.
Geological Formation and Sources
The formation of December’s birthstones occurs in vastly different geological environments, from arid deserts to volcanic rifts, which directly influences their appearance and availability.
Turquoise is a rare, opaque mineral that forms in arid regions where acidic water percolates through rocks containing aluminum and copper. This process occurs in areas with copper-rich geological formations and specific weather conditions that facilitate its creation. The most significant sources include the southwestern United States (notably Arizona and New Mexico), Iran, Egypt, China, Mexico, and parts of Central Asia and Africa. Turquoise is often characterized by its "matrix," a web-like pattern of host rock that becomes part of the gem, adding unique color and texture.
Zircon is a zirconium silicate mineral that forms in igneous and metamorphic rocks. It is found in a variety of locations worldwide, including Australia, Cambodia, Sri Lanka, and the United States. Its durability and resistance to weathering make it one of the oldest minerals on Earth, often used in geological dating.
Tanzanite is a variety of the mineral zoisite and is found exclusively in the Merelani Hills of Tanzania, near Mount Kilimanjaro. Its formation is linked to a unique geological event: the tectonic shift that created the Great Rift Valley. Heat and pressure from this event transformed the original zoisite into the vibrant blue and violet crystals we see today. This singular source makes tanzanite exceptionally rare, with geologists estimating its commercial lifespan to be limited.
Blue Topaz is a silicate mineral of aluminum and fluorine. While topaz crystals can be found in many locations, including Brazil, Nigeria, and Pakistan, the intense blue color for which the December birthstone is known is typically the result of treating colorless or pale blue topaz with radiation and heat. Natural blue topaz is extremely rare. The gem’s formation occurs in igneous rocks, particularly in pegmatites and high-temperature veins.
Gemological Properties
Understanding the physical and chemical properties of these gems is crucial for their identification, valuation, and care. The following table summarizes key gemological data for the primary December birthstones, based on information from the provided sources.
| Gemstone | Chemical Composition | Hardness (Mohs Scale) | Typical Colors | Key Properties & Notes |
|---|---|---|---|---|
| Turquoise | Hydrated phosphate of copper and aluminum (CuAl₆(PO₄)₄(OH)₈·4H₂O) | 5 - 6 | Blue to green | Opaque; often has a matrix; relatively soft, requires careful handling. |
| Zircon | Zirconium silicate (ZrSiO₄) | 6.5 - 7.5 | Various, but colorless is common; blue, golden, brown | High brilliance and fire; can be heat-treated to improve color; durable. |
| Tanzanite | Calcium aluminum hydroxy silicate (Ca₂Al₃(SiO₄)₃(OH)) | 6.5 - 7 | Blue to violet | Trichroic (shows blue, violet, and burgundy); pleochroic; often heat-treated to enhance color. |
| Blue Topaz | Aluminum silicate fluoride hydroxide (Al₂SiO₄(F,OH)₂) | 8 | Sky blue to deep blue | Transparent; typically treated to achieve blue color; very hard and durable. |
Turquoise is prized for its opaque, sky-blue to green hues. Its hardness on the Mohs scale ranges from 5 to 6, making it relatively soft compared to other birthstones. This necessitates careful handling to avoid scratches and impacts. The presence of a matrix, or host rock, is common and can add to the stone's character, though it can also affect its durability.
Zircon is renowned for its exceptional brilliance and fire, which often rivals that of diamond. With a hardness of 6.5 to 7.5, it is quite durable for jewelry. Colorless zircon is sometimes used as a diamond simulant, but it is a distinct natural gem. Blue zircon, a popular December variety, is often achieved through heat treatment of brown zircon.
Tanzanite is celebrated for its mesmerizing trichroism, meaning it displays three different colors—blue, violet, and burgundy—when viewed from different crystallographic directions. Its hardness is 6.5 to 7, making it suitable for jewelry but requiring protection from sharp blows. Most tanzanite on the market has been heat-treated to stabilize its color and remove brownish hues, a standard and accepted practice in the gem trade.
Blue Topaz is one of the hardest December birthstones, with a Mohs hardness of 8. This makes it highly resistant to scratching and ideal for everyday wear. The vibrant blue color of most commercial blue topaz is the result of irradiation and heat treatment of colorless topaz. Natural blue topaz is exceedingly rare and usually very pale.
Symbolism and Metaphysical Beliefs
Across cultures and centuries, each of December’s birthstones has accumulated a rich tapestry of symbolic meanings and metaphysical beliefs, often tied to their color and perceived energies.
Turquoise is universally regarded as a stone of protection, healing, and good fortune. Ancient warriors wore it for safety in battle, and it was believed to ward off evil and negative energy. It is also associated with wisdom, tranquility, and friendship. In many cultures, turquoise is thought to promote mental clarity, relieve mental tension, and increase luck, making it a stone of both physical and spiritual well-being.
Zircon is believed to enhance spiritual growth and wisdom. It is said to help its wearer achieve inner peace and stability. Some traditions hold that zircon can promote prosperity and honor, while its brilliant sparkle is thought to attract success and positive energy.
Tanzanite, as a relatively new gem, has quickly developed a modern mythology centered on transformation and higher consciousness. It is often called the "stone of transformation" and is believed to facilitate a connection between the heart and mind, promoting spiritual awakening and a higher perspective. Its energy is said to be calming and soothing, helping to free the wearer from negativity and expand awareness.
Blue Topaz is associated with calm, clarity, and communication. It is believed to soothe the mind, reduce stress, and promote honest self-expression. In some beliefs, blue topaz is linked to love and affection, making it a popular stone for jewelry given as a gift. Its clear, cool blue is thought to evoke feelings of peace and tranquility, much like a clear winter sky.
While the primary December stones share themes of calm and protection, the historical stones carry their own distinct symbolism. Bloodstone is a stone of courage and strength, Ruby is a stone of vitality and passion, and Onyx is a grounding stone believed to protect from negativity. This diversity allows December-born individuals to choose a stone that resonates with their personal journey and intentions.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of December’s birthstones, and the guidelines vary significantly based on their gemological properties.
Turquoise, with its relatively low hardness (5-6) and porous nature, requires the most care. It should be protected from chemicals, including perfumes, lotions, and household cleaners, which can damage its surface and cause discoloration. Clean turquoise jewelry with a soft, dry cloth. Avoid ultrasonic cleaners and steam cleaning, as these can cause cracking or damage. It is best to store turquoise separately to prevent scratches from harder gems.
Zircon is more durable but can be brittle due to its crystal structure. It is sensitive to sudden temperature changes, which can cause fracturing. Clean zircon with warm water, mild soap, and a soft brush. Avoid ultrasonic cleaners and extreme heat. Store it carefully to prevent chipping.
Tanzanite is somewhat delicate due to its trichroism and cleavage. It should be protected from sharp blows and rough wear. Clean tanzanite with warm, soapy water and a soft brush. Ultrasonic cleaners and steam cleaning are not recommended, as they can cause damage. Given its rarity and value, professional cleaning is advisable for valuable pieces.
Blue Topaz is the most durable of the group, thanks to its hardness of 8. It can withstand more rigorous cleaning methods. It is safe to use warm, soapy water and a soft brush. Ultrasonic cleaners are generally safe, but caution is advised if the stone is set in a delicate setting. Avoid exposing topaz to sudden extreme temperature changes, as this can potentially cause fractures.
For all December birthstones, it is advisable to remove jewelry before engaging in activities that could cause impact or exposure to harsh chemicals, such as gardening, cleaning, or swimming. Regular inspections by a professional jeweler can help ensure settings remain secure and the stones remain in good condition.
Conclusion
December’s birthstones offer a remarkable range of choices, each with its own distinct history, geological origin, and symbolic meaning. From the ancient, protective Turquoise and the brilliantly fiery Zircon to the transformative Tanzanite and the tranquil Blue Topaz, these gems provide a perfect reflection of the month’s cool, serene, and festive spirit. Their journey from the earth’s depths to jewelry boxes around the world is a testament to both geological wonder and human appreciation for beauty and meaning. Whether selected for their aesthetic appeal, historical significance, or metaphysical properties, December’s birthstones are more than just adornments; they are personal talismans that connect the wearer to a legacy of artistry, science, and culture that spans millennia.