The month of December is unique in the world of gemology, holding the distinction of having four official birthstones. While most months are associated with a single gem, December offers a rich palette of blue-toned stones, each with its own distinct history, composition, and allure. This variety provides individuals born in this month with a wide spectrum of choices, from the ancient, opaque beauty of Turquoise to the modern, vibrant brilliance of Tanzanite, Zircon, and Blue Topaz. These four gemstones—Turquoise, Tanzanite, Zircon, and Blue Topaz—collectively represent the cool, serene hues of winter, offering a range of options in terms of durability, price, and personal meaning. Understanding the unique characteristics of each allows for a deeper appreciation of their significance as birthstones and as enduring gems in the world of fine jewelry.
The official recognition of these stones has evolved over time. The modern list of birthstones was standardized in 1912 by the National Association of Jewelers, with subsequent updates adding new gems as they gained popularity or were discovered. For December, the list began with Turquoise and was later expanded to include Zircon in 1952 and Tanzanite in 2002, solidifying the month's status as the one with the most birthstone options. This expansion was driven by a desire to offer consumers more variety in color, style, and affordability, ensuring that every December-born individual could find a gem that resonated with them. This guide will explore the geological origins, gemological properties, historical lore, and practical care of each of these four remarkable December birthstones.
History and Lore
The history of December's birthstones is as varied as the gems themselves, spanning millennia and continents. Turquoise is, by far, the most ancient of the group, with a legacy of reverence that stretches back thousands of years. It was one of the first gemstones to be mined and cherished by ancient civilizations. Sources indicate that Turquoise has been associated with protection, healing, and friendship for millennia. Its distinctive sky-blue to greenish color, often interspersed with a characteristic matrix of host rock, made it instantly recognizable and highly prized. Ancient cultures believed the stone possessed powerful protective qualities, often using it to create amulets and talismans intended to safeguard the wearer from harm. This long-standing association with protection and good fortune cemented its place in history long before the concept of birthstones was formalized.
The journey of Turquoise into the official birthstone list is a story of enduring tradition. It has long been a staple in jewelry across many cultures, from the ancient Egyptians, who adorned their pharaohs with it, to the Native American tribes of the American Southwest, who continue to be renowned for their intricate Turquoise jewelry. Its inclusion in the 1912 standard list was a natural progression, acknowledging its deep-rooted popularity and cultural significance. While Turquoise represents the traditional choice, the other December stones have more recent, yet equally fascinating, histories.
Zircon, another of December's official stones, is one of the oldest minerals on Earth, with crystals dated to billions of years. Historically, confusion often arose between Zircon and other gems like Diamond due to its high refractive index and brilliance, leading to names like "Jacinth" or "Hyacinth." While its history is ancient, its formal recognition as a December birthstone is more modern. The Jewelry Industry Council of America updated the official list in 1952 to include Zircon, likely due to its exceptional sparkle and availability in the desirable blue color that fits the December theme. It is associated with wisdom, prosperity, and good fortune, adding a layer of intellectual and material meaning to its vibrant appearance.
Tanzanite is the newest addition to the December family, earning it the status of a modern birthstone. Its story is one of recent discovery and rapid ascent to fame. Discovered in the Merelani Hills of Tanzania in the mid-20th century, this gemstone's journey to the official list was swift. It was formally added in 2002, a testament to its immense popularity and unique beauty. The gem was initially brought to global attention by the jewelry company Tiffany & Co., which recognized its stunning violet-blue color and marketed it heavily. The lore surrounding Tanzanite is tied to its modernity; it is often linked to themes of transformation, intuition, and spiritual growth, reflecting its recent emergence as a significant gemstone. Its rarity, being found in only one location in the world, adds to its mystique and desirability.
Blue Topaz, while often considered an alternative or secondary birthstone for December, has a rich history of its own. The exact historical origin of blue topaz is unknown, as it has been found throughout history. Its use in jewelry dates back to ancient times, but it was often found in yellow or brown hues. The brilliant, saturated blue that is now popular is typically the result of treatment processes applied to colorless topaz. Its addition to the list of December stones reflects its growing popularity and accessibility. In 2002, when Tanzanite was added, Blue Topaz was already a well-established choice in the market. It is officially recognized as the state gem of Texas, a nod to its significance in the United States. Today, it is celebrated for its clarity, communication, and calmness, offering a durable and affordable blue gem option.
Geological Formation and Sources
The formation of these four gemstones occurs under vastly different geological conditions, which accounts for their unique chemical compositions and physical properties. Turquoise is a secondary mineral that forms in arid regions where acidic, copper-rich water seeps through aluminum-bearing rocks. Over long periods, this process results in the deposition of hydrated copper and aluminum phosphate, creating the nodular or vein-like formations of Turquoise. The most significant sources for Turquoise include the United States, particularly the American Southwest (Arizona, Nevada, and New Mexico), as well as Iran, Egypt, and Tibet. The color and matrix patterns are heavily influenced by the specific mineral composition of the host rock in these locations.
Tanzanite's geological story is incredibly specific, which directly contributes to its rarity. It is a variety of the mineral zoisite and is formed through a unique and complex geological process involving intense heat and pressure, a phenomenon that is believed to have occurred during the formation of Mount Kilimanjaro. This specific set of conditions has only been found in a small, 4-square-kilometer mining area in the Merelani Hills of northern Tanzania. As noted in the sources, Tanzanite is the rarest of the December birthstones because it is mined in this single, limited region. This geographic exclusivity is a primary driver of its value and high price point compared to the other December gems.
Zircon is a mineral that forms within igneous and metamorphic rocks during the cooling of magma. It is one of the oldest minerals on Earth, and its crystals can be found in many parts of the world. The blue variety of zircon, which is the preferred color for December birthstones, is often created by heating brown zircon crystals to high temperatures, a process that removes the brown coloration and produces the desired blue hue. Major sources for Zircon include Cambodia, Sri Lanka, Thailand, and Australia. Its widespread geological occurrence makes it more accessible than Tanzanite, though finding large, high-quality blue stones can still be challenging.
Blue Topaz is a silicate mineral that forms in the cavities and fissures of igneous rocks like granite. Colorless topaz crystals can grow to impressive sizes, which is why large Blue Topaz stones are relatively common and affordable. As mentioned, the vibrant blue color seen in most jewelry today is not typically natural; it is achieved through irradiation and heat treatment of the colorless crystals. This treatment process is stable and permanent. Major mining sources for topaz include Sri Lanka, Brazil, Mexico, Nigeria, and the United States. Its abundance in its natural state, combined with the ability to treat it to achieve a desirable blue color, makes it one of the most budget-friendly options among the December birthstones.
Gemological Properties
Understanding the gemological properties of each stone is crucial for both jewelers and consumers, as these characteristics dictate durability, appearance, and value. The following table summarizes the key properties of the four December birthstones, based on the provided sources.
| Gemstone | Color & Varieties | Mohs Hardness | Symbolism / Meaning |
|---|---|---|---|
| Turquoise | Blue to green (often opaque, sometimes with matrix) | 5 – 6 | Protection, healing, friendship |
| Tanzanite | Violet-blue to deep blue (pleochroic) | 6 – 7 | Transformation, intuition, spiritual growth |
| Blue Topaz | Sky Blue, Swiss Blue, London Blue | 8 | Clarity, communication, calmness |
| Zircon | Brilliant blue (also multi-color) | 6.5 – 7.5 | Wisdom, prosperity, good fortune |
Color is a defining feature for all four gems. Turquoise ranges from a soft sky blue to a greenish-blue, with its color often being mottled or veined by the host rock, known as matrix. Tanzanite is prized for its unique violet-blue hue, which is often described as a rich "velvet" blue. A key property of Tanzanite is its pleochroism, meaning it displays different colors (blue and violet) when viewed from different angles. Blue Topaz comes in a spectrum of blues, from the pale "Sky Blue" to the intensely saturated "Swiss Blue" and the deep, dramatic "London Blue." Zircon, while known for its brilliant blue, can also be found in a variety of other colors, but the blue variety is most associated with December.
Hardness, as measured on the Mohs scale, is a critical indicator of a gem's ability to resist scratching. This is an essential factor for jewelry intended for regular wear, such as rings. Blue Topaz is the clear leader in durability among the December stones, with a hardness of 8. This makes it an excellent choice for everyday wear. Zircon and Tanzanite have similar hardness ratings, ranging from 6.5 to 7.5 and 6 to 7 respectively. While reasonably durable, they are more susceptible to damage from sharp blows than Topaz. Turquoise, with a hardness of only 5 to 6, is the softest of the group. It is more prone to scratching and requires greater care, making it better suited for pendants and earrings rather than rings that might experience frequent impact.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, each of the December birthstones carries a rich tapestry of symbolic meaning and metaphysical beliefs, which have been attributed to them over centuries of use and admiration. These meanings often align with the gem's color, history, and perceived energy, offering wearers a connection to concepts like protection, wisdom, and transformation.
Turquoise is perhaps the most potent in terms of symbolic power. For millennia, it has been regarded as a stone of protection, believed to ward off negative energy and bring good fortune to its bearer. Its lore is deeply connected to healing and friendship. Many cultures viewed it as a sacred stone that could connect the wearer to the spiritual world and promote inner peace. The belief in its protective qualities was so strong that it was often set into shields, swords, and architectural elements, not just personal adornment. For those born in December, Turquoise offers a connection to ancient wisdom and a shield of positivity.
Tanzanite, a gem of the modern era, carries symbolism that speaks to contemporary spiritual pursuits. It is widely associated with transformation and new beginnings. Its unique discovery story and striking color are seen as metaphors for personal growth and awakening. Metaphysical beliefs suggest that Tanzanite can enhance intuition and facilitate a deeper connection to one's higher self. It is often considered a stone for those undergoing significant life changes, providing the clarity and spiritual insight needed to navigate new paths. Its symbolism is one of forward movement and spiritual evolution.
Zircon is linked to qualities of clarity, wisdom, and a sense of balance. Its brilliant sparkle is thought to reflect a clear mind and focused thoughts. Historically, it has been associated with prosperity and good fortune, making it a popular choice for those seeking to attract abundance and success. The belief in its ability to promote wisdom makes it a stone for scholars and those in pursuit of knowledge. By wearing Zircon, a December-born individual may feel connected to the principles of mental acuity and balanced judgment.
Blue Topaz carries a calmer, more serene symbolism. It is associated with clarity of thought, communication, and calmness. This makes it an ideal gem for individuals who wish to express themselves more clearly or seek a sense of peace and tranquility in their lives. Its cool blue color is inherently soothing, and its metaphysical properties are believed to help soothe the mind, release tension, and promote honest, open communication. It is a stone of calm expression and mental relaxation.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of any gemstone jewelry. Due to their differing physical properties, the December birthstones require distinct approaches to cleaning and maintenance.
Turquoise, being the softest of the group (Mohs 5-6), is the most delicate. It is also porous and can be susceptible to chemicals, lotions, and even the oils from skin contact, which can cause discoloration over time. To clean Turquoise, simply use a soft, dry cloth. If necessary, a mild soap and lukewarm water solution can be used, but it must be dried thoroughly and immediately. Avoid ultrasonic cleaners, steam cleaners, and any harsh chemicals. It is best to remove Turquoise jewelry before swimming, showering, or applying cosmetics.
Tanzanite (Mohs 6-7) is considered fragile due to its perfect cleavage in one direction, meaning it can split along internal planes if struck with sufficient force. While it can be worn in rings, it is best placed in earrings or pendants where it is less likely to be knocked. Cleaning should be done with warm water, a mild soap, and a soft brush. As with Turquoise, avoid ultrasonic and steam cleaners.
Zircon (Mohs 6.5-7.5) is also susceptible to chipping because of its cleavage, so it requires gentle handling. However, it is generally durable enough for most jewelry types. The best method for cleaning Zircon is warm soapy water and a soft brush. It is advisable to avoid sudden temperature changes, as this can sometimes cause fracturing in the stone.
Blue Topaz (Mohs 8) is the most durable of the December stones for everyday wear. It is hard and resistant to scratching. However, like Zircon and Tanzanite, it has perfect cleavage, making it vulnerable to chipping from sharp impacts. It is also sometimes treated with irradiation to achieve its blue color, but standard cleaning methods are safe. Warm, soapy water and a soft brush are effective for cleaning Blue Topaz. It is generally safe to use an ultrasonic cleaner, but it is still wise to avoid steam cleaners due to its cleavage.
Conclusion
The four birthstones of December—Turquoise, Tanzanite, Zircon, and Blue Topaz—offer a remarkable diversity of choice, united by the serene and beautiful color blue. From the ancient, protective talisman of Turquoise to the rare, transformative beauty of Tanzanite, each gem provides a unique narrative. Zircon brings brilliant sparkle and a connection to wisdom, while Blue Topaz offers exceptional durability and clarity at an accessible price point. Their varied origins, from the singular mines of Tanzania to deposits around the globe, and their distinct gemological properties create a rich landscape for collectors and jewelry enthusiasts. For anyone born in the final month of the year, these stones provide not just a beautiful adornment but a personal symbol reflecting history, meaning, and individual style.