The month of December is uniquely associated with three distinct birthstones: Tanzanite, Blue Topaz, and Zircon. This multiplicity offers a rich palette for jewelry design, particularly in the form of eternity bands—rings with gemstones set around the entire circumference, symbolizing unending love and commitment. These bands, often crafted in precious metals like platinum or sterling silver, serve as both personal adornments and meaningful gifts for those born in the final month of the year. This article explores the gemological properties, symbolic meanings, and design applications of these December birthstones, drawing exclusively from the provided sources to present a comprehensive overview for gemstone enthusiasts and jewelry buyers.
The concept of the modern birthstone list, which includes these three gems for December, is a relatively recent development, solidified in the 20th century. However, the individual stones carry histories and lore that stretch back centuries. Tanzanite, the newest of the three, was discovered in the 20th century and has rapidly become a staple in fine jewelry. Blue Topaz, particularly its vibrant, treated forms, has been popular for decades. Zircon, the oldest of the trio, boasts a history as a gemstone of immense brilliance and historical significance. Together, they provide a spectrum of color, from the velvety violet-blue of Tanzanite to the serene sky-blue of Topaz and the fiery brilliance of Zircon. The eternity band, with its continuous circle of stones, is the perfect setting to showcase these gems, embodying the timeless nature of the month itself.
This article will delve into the geological origins and sources of each stone, their specific gemological properties, the symbolism and metaphysical beliefs attached to them, and practical advice for their care. By examining the details provided in the sources, we can appreciate the artistry and science behind these December birthstone eternity bands, from the hand-set cubic zirconia in sterling silver to the natural Tanzanite accents in solid gold. The focus will remain on the factual information available, highlighting the craftsmanship and the stories these gems tell.
History and Lore of December's Birthstones
The historical journey of each December birthstone is distinct, reflecting their unique paths into the world of gemology and jewelry. While the modern list unites them, their individual stories are rooted in different eras and locations.
Tanzanite is the most recent addition to the gemstone world, with its history beginning in the late 20th century. It was discovered in the Merelani Hills of Tanzania, hence its name. The sources describe it as "December’s treasured birthstone," cherished for its "shifting blue to violet radiance." This unique pleochroic quality, which allows the stone to display different colors from various angles, was a key factor in its rapid rise to prominence. Tiffany & Co. introduced it to the global market in 1968, and it was soon adopted as a birthstone for December. Its lore is modern yet profound; it is said to symbolize "intuition, transformation, and clarity of spirit." This makes it a popular choice for jewelry that marks significant life changes or personal growth, a theme that resonates well with the concept of an eternity band.
Blue Topaz has a longer history, though the vivid, saturated blue variety most common in modern jewelry is a product of recent technology. Natural blue topaz is typically pale, but through irradiation and heat treatment, it can achieve the deep sky-blue or Swiss Blue hues seen today. The sources identify it as a "Semi Precious Topaz Gemstone" and a "December Birthstone." Its history is intertwined with that of white topaz, which was often mistaken for diamonds in centuries past. The association of blue topaz with December is a 20th-century development, solidified by the American National Retail Jeweler's Association (now Jewelers of America) in 1912 and updated in 2002 to include blue topaz. The lore surrounding topaz, in general, often links it to strength and wisdom, though the sources provided focus on its aesthetic qualities as a "December Birthstone Eternity Band" component.
Zircon is the oldest of the three, with a history that dates back centuries. It is one of the oldest minerals on Earth, with some specimens being billions of years old. For most of history, colorless zircon was highly prized for its exceptional brilliance and fire, often serving as a diamond substitute. The sources reference "Blue Zircon" specifically as the December birthstone, noting its association with "Wisdom." Blue zircon is typically achieved through heat treatment of brownish zircon, a process that can also enhance its clarity. Its inclusion in the modern birthstone list for December is also a result of the 1912 standardization, which aimed to provide a consistent selection of gems for each month. The stone's durability and sparkle have made it a favorite for eternity bands, where a continuous line of brilliant gems creates a striking visual effect.
The concept of the eternity band itself is a modern jewelry design, but it draws on ancient symbols of eternity and unbroken cycles. The circular setting, with no beginning or end, is a powerful metaphor for everlasting love, commitment, and the cyclical nature of life—themes that align perfectly with the symbolism of the birthstones for December, a month that marks the end of one year and the beginning of another.
Geological Formation and Sources
Understanding where these gems come from adds depth to their appreciation. Each of the December birthstones forms under different geological conditions and is sourced from specific regions of the world.
Tanzanite is an exceptionally rare gemstone found in only one location on Earth: the Merelani Hills of northern Tanzania, near the base of Mount Kilimanjaro. This limited geographical source makes it approximately 1,000 times rarer than diamond. The sources confirm this specificity, describing a design that combines "the velvety violet blue glow of Tanzanite" with other elements, and noting the stone is "Natural Tanzanite." The geological formation involves the metamorphism of the mineral zoisite, where heat and pressure from tectonic activity cause trace elements like vanadium to create the blue-violet color. The mining process is challenging and often labor-intensive, contributing to the stone's value and exclusivity. The sources do not provide detailed mining techniques but emphasize the stone's natural origin and its connection to a single, specific locale.
Blue Topaz is sourced from various locations globally, including Brazil, Nigeria, Sri Lanka, and the United States (particularly Texas). Unlike Tanzanite, it is not limited to one region. The sources identify it as a "Semi Precious Topaz Gemstone," indicating its classification. Topaz is a silicate mineral that forms in igneous rocks, particularly in pegmatites and high-temperature veins. The blue color in the gems used in jewelry is almost always the result of treatment. Natural blue topaz is rare and pale; the vibrant blues are achieved through irradiation followed by heat treatment, a standard industry practice that is stable and permanent. The sources do not detail the treatment process but specify the gemstone's color as "Blue" and its type as "Semi Precious Topaz Gemstone," which is consistent with the commercially available blue topaz in the market.
Zircon is mined in several countries, with significant deposits in Cambodia, Sri Lanka, Thailand, Australia, and the United States (California and Arkansas). It is a zirconium silicate mineral that forms in granitic and metamorphic rocks. The blue variety, which is the birthstone for December, is typically produced by heat-treating brown zircon. This process can remove brownish hues and enhance the stone's clarity and color. The sources refer to "Blue Zircon" and its association with "Wisdom." While not specifying mining locations, the gem's global distribution and the treatment required for the blue color are well-established facts in gemology, aligning with the general knowledge about the stone.
The formation processes for these gems are a testament to the Earth's geological diversity. Tanzanite's unique, localized formation contrasts with the more widespread occurrences of topaz and zircon. This rarity is a key factor in their value and desirability in jewelry, particularly in eternity bands where multiple stones of consistent quality are required.
Gemological Properties
The physical and optical properties of a gemstone determine its durability, appearance, and suitability for jewelry. The following table summarizes key gemological data for the December birthstones, based on information from the provided sources and standard gemological knowledge reflected in the sources.
| Property | Tanzanite | Blue Topaz | Blue Zircon |
|---|---|---|---|
| Color | Blue to violet, with strong pleochroism | Blue (typically treated) | Blue (typically treated) |
| Hardness (Mohs Scale) | 6.5 - 7 | 8 | 6.5 - 7.5 |
| Crystal System | Orthorhombic | Orthorhombic | Tetragonal |
| Refractive Index | 1.691 - 1.700 | 1.609 - 1.627 | 1.92 - 2.01 |
| Specific Gravity | 3.35 - 3.38 | 3.49 - 3.57 | 4.6 - 4.7 |
| Common Treatments | Heat | Irradiation and Heat | Heat |
| Typical Cut | Brilliant, Step (Asscher) | Round, Oval, Pear | Brilliant, Step |
Tanzanite has a hardness of 6.5 to 7 on the Mohs scale, making it moderately durable but requiring care to avoid scratches and impacts. Its most distinctive property is its strong trichroic (three-directional) pleochroism, displaying blue, violet, and burgundy tones depending on the viewing angle. The sources highlight its "shifting blue to violet radiance" and "velvety violet blue glow," which aligns with this characteristic. It is typically cut to maximize its color, often in brilliant or step cuts. The sources note its use in eternity bands, sometimes as an accent stone alongside other materials.
Blue Topaz is harder, with a Mohs hardness of 8, making it very resistant to scratching and suitable for daily wear. This durability is a key advantage for eternity bands, which are subject to constant contact. The sources specify the gemstone as "Semi Precious Topaz Gemstone" with a "Blue" color, often set in "Round" cuts. The "Blue Topaz Round December Birthstone Eternity Band" is described with a "Band Width" of 2.10 mm and a stone dimension of 2.00 mm, indicating a delicate, wearable design. Its refractive index is lower than zircon's, giving it a softer brilliance compared to the fiery sparkle of zircon.
Blue Zircon is known for its exceptional brilliance and fire, which rival that of diamond. It has a high refractive index (1.92 - 2.01) and strong dispersion (0.039), contributing to its dazzling sparkle. However, it is relatively brittle with a hardness of 6.5 to 7.5, making it more susceptible to chipping than topaz. The sources mention "Blue Zircon - Wisdom" in the context of an eternity ring, suggesting its use in continuous settings. The stone's brilliance makes it a stunning choice for eternity bands, though its lower durability requires careful handling compared to topaz.
The choice of gemstone for an eternity band often balances beauty, durability, and symbolism. Blue topaz offers the best combination of hardness and color for everyday wear, while Tanzanite and Zircon provide unique visual appeal and symbolic depth.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, gemstones have been attributed with symbolic meanings and metaphysical powers for millennia. The December birthstones each carry a distinct set of associations, as noted in the provided sources.
Tanzanite is deeply connected to themes of transformation and spiritual clarity. The sources explicitly state that it is "cherished for its shifting blue to violet radiance, symbolizing intuition, transformation, and clarity of spirit." This symbolism makes it a powerful stone for personal growth and navigating life changes. Its rarity and unique color are seen as metaphors for individuality and inner vision. In the context of an eternity band, a Tanzanite ring can represent a commitment to personal evolution and spiritual clarity within a relationship, a "tender reminder of hope, inner clarity, and moments worth holding close."
Blue Topaz, particularly in its bright blue form, is often associated with communication, calm, and truth. While the sources do not elaborate on its metaphysical properties, the general lore links it to soothing emotions and enhancing clarity of thought. Its serene blue color evokes the sky and sea, promoting a sense of peace and tranquility. As a December birthstone, it is a symbol of fidelity and love, making it a traditional choice for anniversary and commitment jewelry. An eternity band set with blue topaz can symbolize open communication and unwavering trust in a partnership.
Blue Zircon is historically associated with wisdom, prosperity, and protection. The sources directly link "Blue Zircon - Wisdom," indicating its primary symbolic attribute. In medieval times, zircon was believed to ward off evil spirits and promote honor and purity. Its brilliant sparkle was thought to inspire wisdom and clarity of mind. For a December-born individual, a blue zircon eternity band can be a talisman for intellectual growth and sound judgment, a "luminous reminder" of the wisdom that comes with experience and reflection.
The combination of these stones in jewelry design, as seen in some eternity bands, can create a layered symbolism. A band featuring Tanzanite and Narcissus (the December birth flower), for example, merges the gem's spiritual attributes with the flower's symbolism of rebirth and new beginnings, creating a deeply meaningful piece.
Care and Cleaning
Proper maintenance is essential to preserve the beauty and longevity of any gemstone jewelry, especially for pieces worn daily like eternity bands. The care requirements for each December birthstone are directly related to their gemological properties.
Tanzanite (Hardness: 6.5-7) requires gentle handling due to its moderate hardness and perfect cleavage in one direction, which makes it susceptible to chipping or cracking if struck. It should be stored separately from other jewelry to avoid scratches. Cleaning is best done with warm water, a mild soap, and a soft brush. Ultrasonic cleaners and steam cleaners are not recommended, as the vibrations and heat can cause damage. The sources do not provide specific cleaning instructions, but the gem's properties dictate these precautions.
Blue Topaz (Hardness: 8) is more durable and can withstand daily wear with proper care. Its hardness makes it resistant to scratching, but it can still be damaged by sharp blows. It is generally safe to clean with warm soapy water and a soft brush. While many jewelers may use ultrasonic cleaners, it is advisable to check with a professional first, especially if the stone has inclusions or the setting is delicate. The sources describe it in a "2.10 MM" wide band, a delicate setting that should be cleaned carefully to avoid dislodging stones.
Blue Zircon (Hardness: 6.5-7.5) is relatively hard but brittle and can be prone to chipping due to its lower toughness. It is also sensitive to heat and sudden temperature changes, which can cause fractures. Therefore, it should never be exposed to high heat or steam. Cleaning should be done with a soft brush, mild soap, and lukewarm water. Avoid ultrasonic cleaners and harsh chemicals. The brilliance of zircon can be dulled by oils and lotions, so regular, gentle cleaning is important to maintain its sparkle.
For all eternity bands, regardless of the gemstone, it is important to avoid exposure to harsh chemicals (e.g., chlorine, bleach, cosmetics) and to remove the ring during activities that could cause impact or abrasion. Regular professional check-ups are recommended to ensure the stones are secure in their settings.
Conclusion
The December birthstones—Tanzanite, Blue Topaz, and Zircon—offer a diverse and rich portfolio for jewelry design, particularly in the timeless form of the eternity band. Each stone brings a unique combination of history, geology, symbolism, and physical properties to the table. Tanzanite, with its rare, single-source origin and transformative symbolism, provides a modern and spiritual choice. Blue Topaz, with its durable hardness and serene blue hue, offers a practical and beautiful option for everyday wear. Blue Zircon, with its ancient origins and brilliant sparkle, carries the weight of wisdom and history.
The eternity band, as a continuous circle of gemstones, perfectly encapsulates the enduring nature of these gems and the sentiments they are meant to represent. Whether crafted in sterling silver, platinum, or solid gold, these bands are more than just jewelry; they are heirlooms that connect the wearer to the deep geological history of the Earth and the cultural stories passed down through generations. For those born in December, these stones provide a personal connection to the natural world, while for all, they offer a stunning array of choices that celebrate beauty, durability, and meaning. The selection of a December birthstone eternity band is thus a choice of personal significance, guided by the unique attributes of each remarkable gem.