The concept of tradition, deeply woven into the fabric of human culture, finds a particularly resonant expression in the world of gemstones. For the month of December, the birthstones traditionally associated with this time of year—Turquoise, Tanzanite, and Zircon—are not merely decorative objects but vessels of history, belief, and geological marvel. The term "traditional," as it applies to these gemstones, signifies a heritage passed down through generations, embodying customs, beliefs, and practices that have stood the test of time. According to dictionary definitions, tradition refers to "the handing down of statements, beliefs, legends, customs, information, etc., from generation to generation, especially by word of mouth or by practice." A traditional artifact, therefore, is one that is "of, relating to, or in accord with tradition," and "handed down by tradition." This article explores the traditional significance of December's birthstones, delving into their historical lore, geological origins, gemological properties, and the enduring symbolism that makes them timeless treasures. We will examine how these stones, each with a unique story, encapsulate the very essence of what it means to be traditional.
Historical Origins and the Path to Birthstone Status
The journey of a gemstone to becoming a traditional birthstone is often a long and winding one, rooted in ancient texts and cultural practices. The modern list of birthstones, standardized in the early 20th century by the National Association of Jewelers (now Jewelers of America), was largely based on historical and biblical traditions. For December, the primary traditional stone is Turquoise, a gem revered for millennia. Its use dates back to ancient Egypt, where it was used in elaborate jewelry and amulets, and to Persia, where it was considered a symbol of protection and wealth. The name "turquoise" itself is derived from the French pierre turquoise, meaning "Turkish stone," reflecting its trade route through Turkey from its primary source in the Sinai Peninsula. This long-established history firmly places Turquoise within the definition of tradition: a custom and belief "handed down from generation to generation."
In the 20th century, the list of traditional birthstones was expanded to include newer stones that gained popularity and significance. Tanzanite, a relatively recent discovery, was added to the list of modern birthstones for December. While not "traditional" in the ancient sense, its rapid adoption into the birthstone canon demonstrates how traditions can evolve. Its story, however, is deeply tied to a specific location and a unique geological event, creating a new tradition in the gem world. Zircon, the third traditional December stone, has an even more ancient lineage, often confused with cubic zirconia due to its name but a natural gemstone with a history of its own. The tradition of Zircon as a protective stone dates back centuries, and its use in European jewelry during the Middle Ages aligns with the concept of a "time-honored orthodox" practice.
The transition of these stones into birthstones is a process of codifying existing cultural traditions. The 1912 list by the National Association of Jewelers was based on the 18th-century St. Jerome's list, which itself was inspired by the Breastplate of Aaron described in the Book of Exodus. This historical continuity underscores the traditional nature of birthstones, connecting modern wearers to an ancient lineage of belief and adornment.
Geological Formation and Mining Sources
The traditional character of these gemstones is not only cultural but also geological. Each is formed under specific, often rare, conditions that contribute to their unique properties and value.
Turquoise is a hydrous phosphate of copper and aluminum, formed in arid regions where acidic, copper-rich groundwater percolates through rocks containing aluminum and phosphorus. Over millions of years, this process creates the blue-to-green mineral veins. Historically, the most prized turquoise came from the Sinai Peninsula, mined by the ancient Egyptians. Today, major sources include the United States (particularly Arizona, New Mexico, and Nevada), Iran, and China. The traditional mining methods in some of these regions, such as those used by Native American tribes in the American Southwest, are themselves a form of cultural tradition, passed down through generations of artisans.
Tanzanite is a variety of the mineral zoisite, and its formation is one of the most geologically unique stories in the gem world. It is found in only one location on Earth: the Merelani Hills of Northern Tanzania, near the base of Mount Kilimanjaro. Its formation is linked to a tectonic event that occurred approximately 585 million years ago, during the Neoproterozoic Era, when the supercontinent Rodinia was breaking apart. This event subjected the rocks to intense heat and pressure, transforming the original zoisite into the vibrant blue-violet crystals known today as tanzanite. The mining of tanzanite is a modern, industrial operation, but the gem's exclusivity to a single location adds a layer of modern tradition and scarcity.
Zircon is a zirconium silicate (ZrSiO₄) and is one of the oldest minerals on Earth, with some crystals dating back over 4 billion years. It forms in igneous and metamorphic rocks, commonly found in granite, syenite, and gneiss. Zircon occurs in a wide range of colors, but the traditional December birthstone is the blue variety, which is typically heat-treated to enhance its color from brown or yellow. Major sources for gem-quality zircon include Cambodia, Sri Lanka, Thailand, Australia, and the United States. The longevity of zircon as a mineral mirrors the enduring nature of the traditions associated with it.
Gemological Properties: The Science of Tradition
The physical properties of these gemstones are what make them suitable for jewelry and, consequently, for their traditional roles. Their durability, color, and optical characteristics are central to their appeal.
Turquoise
Turquoise is prized for its unique sky-blue to greenish-blue color, which is caused by the presence of copper. It is an opaque gemstone, meaning light does not pass through it, and it often features a distinctive "spiderweb" or "matrix" pattern of darker veins from the host rock. On the Mohs scale of hardness, turquoise is relatively soft, ranging from 5 to 6. This makes it susceptible to scratching and requires careful handling. Its chemical composition is a hydrated copper aluminum phosphate. The traditional value of turquoise is heavily influenced by its color and matrix, with a uniform, vibrant blue being the most sought after.
Tanzanite
Tanzanite is a transparent to translucent gemstone known for its striking blue-to-violet hue, a color caused by vanadium impurities and heat treatment. It exhibits strong trichroism, meaning it can display three different colors—blue, violet, and burgundy—depending on the crystal orientation. With a Mohs hardness of 6.5 to 7, it is more durable than turquoise but still requires care to avoid chipping or abrasion. Its chemical composition is calcium aluminum hydroxyl silicate. The most prized tanzanite is a deep, saturated blue with a slight violet undertone, often found in larger carat sizes.
Zircon
Zircon is a brilliant and lustrous gemstone with a high refractive index, giving it exceptional sparkle that can rival diamond. The blue variety, which is the traditional December stone, is typically heat-treated to achieve its color. Natural blue zircon is rare. Zircon has a hardness of 7.5 on the Mohs scale, making it quite durable for jewelry, though it can be brittle and prone to chipping if struck. Its chemical composition is ZrSiO₄. The brilliance and fire of zircon are its defining gemological features, contributing to its long-standing use in fine jewelry.
The following table summarizes the key gemological properties of the traditional December birthstones:
| Gemstone | Chemical Composition | Mohs Hardness | Color | Key Characteristic |
|---|---|---|---|---|
| Turquoise | Hydrous copper aluminum phosphate (CuAl₆(PO₄)₄(OH)₈·4H₂O) | 5 - 6 | Sky-blue to greenish-blue, often with matrix | Opaque, often with a distinctive matrix pattern |
| Tanzanite | Calcium aluminum hydroxyl silicate (Ca₂Al₃(SiO₄)₃(OH)) | 6.5 - 7 | Blue to violet (trichroic) | Strong trichroism, transparency |
| Zircon | Zirconium silicate (ZrSiO₄) | 7.5 | Blue (often heat-treated), also colorless, brown, etc. | High brilliance and refractive index, durability |
Symbolism and Metaphysical Beliefs
The traditional status of these gemstones is inextricably linked to the beliefs and symbolism attached to them over centuries. These metaphysical properties are a core part of their cultural tradition.
Turquoise is perhaps the most symbolically rich of the three. Across many cultures, it has been regarded as a talisman of protection, health, and good fortune. In ancient Persia, it was worn as an amulet to ward off the "evil eye" and was believed to bring rain and protect riders from falls. For Native American tribes, turquoise is a sacred stone, representing the sky, water, and earth. It is used in ceremonies and is believed to connect the wearer to the spiritual world. The traditional belief in turquoise's protective power is a direct example of a custom "handed down from generation to generation."
Tanzanite, as a modern addition, has quickly developed its own set of symbolic meanings. Often associated with transformation, intuition, and spiritual awakening, it is said to facilitate a connection between the heart and mind. Its unique color, discovered only in the 20th century, has led to it being called the "stone of a generation," representing a new tradition. Some modern sources suggest it promotes calmness and clarity, though this is not a belief rooted in ancient tradition.
Zircon has a long history as a stone of wisdom, honor, and purity. In medieval Europe, it was believed to promote honor, wealth, and wisdom in the wearer. It was also thought to aid in sleep and ward off evil spirits. The blue zircon, in particular, is associated with tranquility and peace. These traditional beliefs align with the gem's historical use in royal and religious jewelry, where it symbolized authority and divine favor.
Care and Cleaning: Preserving Traditional Treasures
The traditional value of these gemstones is preserved through proper care, which is dictated by their gemological properties. The methods of care have also been passed down as part of the tradition of jewelry maintenance.
Turquoise, due to its relative softness and porosity, requires gentle care. It should be cleaned with a soft, dry cloth. Avoid harsh chemicals, ultrasonic cleaners, and prolonged exposure to water, lotions, or cosmetics, which can damage the stone or alter its color. Storing turquoise separately from other jewelry will prevent scratches.
Tanzanite, while harder than turquoise, has perfect cleavage in one direction, making it vulnerable to chipping or splitting if struck. It is best cleaned with warm, soapy water and a soft brush. Ultrasonic cleaners and steam cleaners are not recommended. Given its relative softness compared to diamonds or sapphires, it is best set in protective settings like bezels for everyday wear.
Zircon is more durable, with a hardness of 7.5, but its brittleness means it can fracture under impact. It is generally safe to clean with warm, soapy water and a soft brush. However, extreme temperature changes can cause damage, so it should not be exposed to sudden heat. As with all gemstones, it is wise to have settings inspected regularly by a professional jeweler to ensure the stone is secure.
The practice of caring for these stones according to their specific needs is a modern extension of the traditional respect for the materials and the craftsmanship that created the jewelry.
Conclusion
The traditional December birthstones—Turquoise, Tanzanite, and Zircon—each tell a story that aligns with the multifaceted definition of "traditional." Turquoise embodies ancient customs and protective beliefs passed down through millennia, from Egyptian pharaohs to Native American tribes. Zircon represents a time-honored mineral with a legacy of wisdom and honor in European lore. Tanzanite, while modern, has rapidly forged its own tradition, tied to a specific geological epoch and a single, sacred location in Tanzania. Together, they form a triad that represents both the enduring nature of tradition and its capacity for evolution. Their gemological properties, from turquoise's soft, matrix-filled opacity to zircon's brilliant sparkle and tanzanite's trichroic magic, provide the physical foundation for their symbolic and cultural significance. For the gemstone enthusiast, the jewelry buyer, and the student of gemology, these stones are more than birthstones; they are tangible connections to history, geology, and the human desire to imbue natural objects with meaning and tradition.