For those born on December 27, the birthstone assignment is not a single gem but a trio of remarkable stones: Tanzanite, Turquoise, and Zircon. This unique combination offers a spectrum of blues, from the sky-like hues of turquoise to the deep violet-blue of tanzanite and the bright, clear tones of zircon. Each stone carries its own distinct history, geological origin, and set of metaphysical beliefs, providing a rich palette of choices for jewelry enthusiasts and those interested in the cultural significance of gemstones. The inclusion of multiple stones for this date reflects a broader trend in modern birthstone lists, which prioritize variety and personal preference over a singular, rigid assignment. This article will explore the historical context, geological formation, gemological properties, and symbolic meanings of these three December 27 birthstones, drawing from authoritative gemological sources to provide a comprehensive overview.
History and Lore
The historical narratives of Tanzanite, Turquoise, and Zircon span millennia, from ancient civilizations to a modern discovery in the 20th century. Each stone has been woven into the cultural fabric of different societies, accruing layers of lore and significance.
Tanzanite is a gemstone of recent discovery, which has quickly become a cornerstone of modern jewelry. It was first found in 1967 in the Merelani Hills of Tanzania, a location so unique that the gemstone was named after its country of origin. Geologically, it is a variety of the mineral zoisite, prized for its captivating blue and purple hues. Its rapid ascent to fame is a testament to its distinctive color and the effective marketing that followed its discovery. Unlike ancient stones, its history is largely documented in the latter half of the 20th century, yet it has already established a strong presence in the gemological world.
Turquoise, in stark contrast, boasts a history that stretches back millennia. This semi-translucent to opaque gem has been cherished by numerous ancient cultures. The pharaohs and rulers of ancient Egypt adorned themselves with turquoise, valuing its striking blue-green color. In China, artisans were carving turquoise more than 3,000 years ago. The stone’s lore is rich with protective attributes. From the 13th century onward, it was believed to safeguard the wearer from falls, particularly from horses, and was thought to break into pieces when disaster approached. Hindu mystics associated it with wealth, believing that seeing a turquoise after the new moon would ensure fantastic fortune. For Native American cultures, particularly the Apache, turquoise was deeply spiritual; they believed it could be found by following a rainbow to its end, linking it to celestial phenomena and good fortune.
Zircon offers a dazzling array of colors and a history that is both long and sometimes misunderstood. While it is one of the traditional December birthstones, its history is often overshadowed by its similarity in name to the synthetic cubic zirconia, a common diamond simulant. However, natural zircon is one of the oldest minerals on Earth, with some specimens dating back billions of years. Historically, zircon has been valued for its brilliance and fire, which rival that of diamonds. It has been used in jewelry for centuries, though its story is less documented in specific ancient lore compared to turquoise. Its association with clarity, wisdom, and balance is a more modern interpretation, building on its physical properties of light dispersion.
Geological Formation and Sources
Understanding where these gemstones originate provides insight into their rarity and value. Each has a distinct geological backstory and is mined in specific, often limited, locations around the world.
Tanzanite has an exceptionally restricted geographic origin. It is found exclusively in the Merelani Hills of northern Tanzania, near the base of Mount Kilimanjaro. This single-source locality makes the gemstone inherently rare. It forms through a complex geological process involving the heating of zoisite, which is altered by the presence of trace elements like vanadium, which imparts its signature blue and violet colors. The mining of tanzanite is concentrated in a small area, which influences its market availability and price.
Turquoise is a phosphate mineral that forms in arid regions where acidic water percolates through rocks containing aluminum and copper. It is found worldwide, with significant deposits in countries including Iran, the United States (particularly in the southwestern states like Arizona and New Mexico), Tibet, and India. Iranian turquoise, especially from the Nishapur region, is historically renowned for its pure sky blue color. American turquoise often exhibits a greenish-blue hue and frequently contains a distinctive brown or black matrix—the remnants of the host rock. The wide geographic distribution of turquoise contributes to its long history of use across various cultures.
Zircon is a common mineral found in many igneous and metamorphic rocks. Significant gem-quality deposits are located in Sri Lanka, Cambodia, and Australia. It is also found in other locations worldwide. Unlike tanzanite, which is limited to one country, zircon has a broader global distribution, though high-quality gem material is still prized and can be rare. Its formation occurs in a variety of geological settings, which contributes to the wide range of colors it can display, from colorless to yellow, brown, red, and blue.
Gemological Properties
The physical and optical properties of a gemstone determine its durability, appearance, and care requirements. The following table summarizes key gemological data for Tanzanite, Turquoise, and Zircon, based on information from authoritative sources.
| Property | Tanzanite | Turquoise | Zircon |
|---|---|---|---|
| Mineral Group | Zoisite (a variety of) | Phosphate | Zirconium Silicate |
| Chemical Formula | Ca₂Al₃(SiO₄)₃(OH) | CuAl₆(PO₄)₄(OH)₈·4H₂O | ZrSiO₄ |
| Mohs Hardness | 6 to 7 | 5 to 6 | 6.5 to 7.5 |
| Color Range | Blue to violet | Sky blue to greenish-blue | Blue (also colorless, yellow, brown, red) |
| Crystal System | Orthorhombic | Triclinic | Tetragonal |
| Transparency | Transparent to translucent | Opaque to semi-translucent | Transparent to translucent |
| Common Treatments | Heat treatment is standard and accepted. | Stabilization (impregnation) is common to enhance durability and color. | Heat treatment is common to improve color and clarity. |
| Durability Notes | Prone to chipping due to cleavage; requires careful setting. | Relatively soft and porous; sensitive to chemicals, heat, and moisture. | Can be brittle; best in protected settings. |
Tanzanite has a Mohs hardness of 6 to 7, making it moderately durable but susceptible to chipping due to its cleavage. It is almost always heat-treated to enhance its blue and violet colors, a process that is universally accepted in the gem trade. Its pleochroism (showing different colors from different angles) is a notable characteristic, typically displaying blue, violet, and reddish tones.
Turquoise is the softest of the three, with a hardness of 5 to 6. Its porous nature makes it susceptible to damage from chemicals, cosmetics, and even the oils from skin contact. Most commercial turquoise is stabilized, meaning it is impregnated with a clear resin or wax to improve its durability, color stability, and luster. Natural, untreated turquoise is rarer and more valuable. The presence of matrix (the host rock) is a natural characteristic and can be a valued part of the gem's appearance.
Zircon is the hardest of the three, with a Mohs hardness of 6.5 to 7.5, but it is brittle and can be prone to chipping at the edges. It is known for its high refractive index and strong dispersion, which gives it a brilliant sparkle often compared to that of a diamond. Most blue zircon on the market is heat-treated from brown zircon, a standard and permanent treatment. It is also sensitive to ultrasonic and steam cleaning due to its brittleness.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, these gemstones are imbued with symbolic meanings and metaphysical beliefs that have been passed down through generations.
Tanzanite is often associated with transformation and new beginnings. Its discovery in the 20th century and its rapid rise to prominence symbolize modernity and change. Metaphysically, it is believed to facilitate spiritual awakening, enhance intuition, and promote emotional healing. For those born on December 27, which falls under the Capricorn zodiac sign, tanzanite is said to support ambition, focus, and clarity, helping to ground lofty goals in practical action.
Turquoise is universally recognized as a stone of protection, good fortune, and friendship. Its historical lore is deeply rooted in these themes, from ancient Egyptian amulets to Native American spiritual practices. It is believed to ward off negative energy, promote calmness, and ensure the wearer's safety. For the Sagittarius zodiac sign (which covers part of December), turquoise is linked to truth-seeking and wisdom, aligning with the sign's philosophical nature.
Zircon is associated with clarity, wisdom, and balance. Its brilliant sparkle is thought to enhance mental clarity and focus. Some traditions believe it can help with spiritual grounding and attract prosperity. Its ability to display a range of colors lends itself to a symbolism of versatility and adaptability, making it a stone of balance between different aspects of life.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of these gemstones, given their distinct physical properties.
Tanzanite requires gentle handling due to its cleavage and moderate hardness. It should be protected from sharp blows and extreme temperature changes. Cleaning should be done with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaning, as the vibrations and heat can cause damage. It is best to store tanzanite jewelry separately to prevent scratches from harder gems.
Turquoise is the most delicate of the three and demands careful attention. It should be kept away from chemicals, including perfumes, lotions, and cleaning agents, which can damage its surface and alter its color. Warm, soapy water and a soft cloth are sufficient for cleaning. It is advisable to remove turquoise jewelry before engaging in physical activities or household chores. The stone can be sensitive to prolonged exposure to water and sunlight, which may cause fading or cracking over time.
Zircon, while harder, is brittle. It should be handled with care to avoid knocks that could chip the edges. Cleaning can be done with warm, soapy water and a soft brush. As with tanzanite, avoid ultrasonic and steam cleaners to prevent potential damage from vibrations and thermal shock. Storing zircon pieces in a padded jewelry box will help protect them from scratches and impacts.
Conclusion
The December 27 birthstones—Tanzanite, Turquoise, and Zircon—offer a remarkable diversity in color, history, and meaning. From the ancient, protective lore of turquoise to the modern, transformative symbolism of tanzanite and the brilliant, clarifying properties of zircon, each gemstone provides a unique connection to the wearer's birth date. Their geological origins, from the singular valley in Tanzania to widespread global deposits, add to their intrigue. Understanding their gemological properties, including hardness and care requirements, is crucial for preserving their beauty. Whether chosen for its historical significance, vibrant color, or metaphysical attributes, this trio of gemstones ensures that those born on December 27 have a wealth of beautiful and meaningful options to celebrate their birth month.