The tradition of assigning specific gemstones to each day of the month is a modern extension of the long-standing practice of birthstones by month. For those born on December 6th, the celestial calendar offers a unique and captivating selection: tanzanite, turquoise, and zircon. These three gemstones, all celebrated for their stunning blue hues, provide a diverse palette of color, history, and meaning. While turquoise and zircon are traditional December birthstones, tanzanite was added as a more recent addition, offering a modern and vibrant alternative. This article delves into the properties, origins, symbolism, and care of these three remarkable gemstones, providing a comprehensive guide for enthusiasts, collectors, and those born on this auspicious day.
History and Lore
The association of gemstones with specific dates is rooted in ancient traditions, most notably the biblical description of the High Priest's breastplate in the Book of Exodus, which featured twelve stones representing the tribes of Israel. Over centuries, this concept evolved, leading to the modern list of monthly birthstones. The December 6th trio reflects this rich tapestry, blending ancient reverence with contemporary discovery.
Turquoise: An Ancient Talisman Turquoise is one of the oldest known gemstones in human history, with a legacy spanning thousands of years. Its use can be traced back to ancient Egypt, where it was cherished by royalty and believed to offer protection and spiritual guidance. The stone's name itself derives from the French pierre turquoise, meaning "Turkish stone," referencing its importation into Europe through Turkey from Persian mines. Beyond the Middle East, turquoise held profound significance in Native American cultures, where it was considered a sacred stone symbolizing life, health, and protection. For centuries, it has been worn as a talisman to ward off negative energy and bring good fortune, making it a cornerstone of the December birthstone tradition.
Zircon: The Oldest Mineral Zircon is not only one of the oldest December birthstones but also one of the oldest minerals on Earth. Some zircon crystals have been dated to be over 4.4 billion years old, making them a tangible link to our planet's earliest history. Historically, zircon was often confused with other gems like diamond or spinel due to its high brilliance and fire. In medieval times, it was believed to promote honor, purity, and wisdom, and to protect the wearer from harm. The blue variety of zircon, which is the most popular for December, is typically heat-treated to achieve its vibrant color, a practice that has been refined over decades to enhance its natural beauty.
Tanzanite: A Modern Marvel In stark contrast to its ancient counterparts, tanzanite is a relative newcomer to the gemstone world. Discovered in the Merelani Hills of Tanzania in 1967, this gem was introduced to the global market in the early 1970s. Its rapid rise to fame is a testament to its extraordinary beauty and rarity. The gem was initially marketed by Tiffany & Co., which recognized its potential and named it after its country of origin. Tanzanite was officially added to the list of December birthstones in 2002, providing a modern and exclusive option for those born in the month. Its unique violet-blue color and single-source origin have made it a symbol of luxury and a prized addition to fine jewelry collections.
Geological Formation and Sources
The origins of these gemstones are as diverse as their appearances, shaped by distinct geological processes and found in specific regions of the world.
Turquoise Formation and Sources Turquoise is a secondary mineral formed through the interaction of water-rich solutions with aluminum and copper-bearing rocks, typically in arid climates. This process, known as percolation, occurs over millions of years, allowing the minerals to crystallize and form the characteristic nodules or veins often found in host rock. Major sources of turquoise include the United States (notably Arizona, Nevada, and New Mexico), Iran, and China. American turquoise, particularly from the Southwest, is renowned for its matrix patterns—web-like inclusions of the host rock that create unique designs. The quality and color of turquoise are heavily influenced by its mineral composition; a higher copper content yields a more vibrant blue, while iron can lead to greenish hues.
Zircon Formation and Sources Zircon is a zirconium silicate mineral that forms in igneous and metamorphic rocks. It is a common accessory mineral in granites and syenites and can also be found in alluvial deposits, where it has been eroded from its original host rock. The blue zircon used in jewelry is almost always heat-treated from brown or yellow zircon crystals. The primary sources of zircon include Australia (which produces the majority of the world's gem-quality zircon), Sri Lanka, and Cambodia. The heat treatment process, typically conducted at high temperatures (around 900-1000°C), is stable and permanent, resulting in a beautiful blue color that is highly prized for its brilliance and fire.
Tanzanite Formation and Sources Tanzanite's formation is a geological anomaly. It is found in only one location on Earth: the Merelani Hills in northern Tanzania, near Mount Kilimanjaro. The gem forms under specific conditions where the mineral zoisite is subjected to intense heat and pressure, which transforms it into the violet-blue variety known as tanzanite. This unique geological event is estimated to have occurred between 500 and 600 million years ago. The scarcity of this single-source deposit makes tanzanite over a thousand times rarer than diamond. Its limited geographic origin adds to its allure and value, making it a true gemological wonder.
Gemological Properties
Understanding the physical and optical characteristics of these gemstones is essential for appreciating their beauty and ensuring proper care. The following table summarizes their key gemological properties, as derived from expert sources.
| Property | Turquoise | Zircon (Blue) | Tanzanite |
|---|---|---|---|
| Color | Sky blue to greenish-blue | Vivid blue (heat-treated) | Rich violet-blue (pleochroic) |
| Hardness (Mohs) | 5 - 6 | 6 - 7.5 | 6.5 - 7 |
| Luster | Waxy to dull | Vitreous (glassy) | Vitreous to adamantine |
| Transparency | Opaque to slightly translucent | Transparent to translucent | Transparent |
| Cleavage | None (brittle) | Poor | Perfect (prone to splitting) |
| Specific Gravity | 2.6 - 2.8 | 3.9 - 4.7 | 3.35 |
| Refractive Index | 1.61 - 1.65 | 1.92 - 2.01 | 1.69 - 1.70 |
Turquoise is a relatively soft and porous stone, making it susceptible to scratches and chemical damage. Its opacity and waxy luster are characteristic of its composition, which often includes water and copper. To improve durability and color, turquoise is frequently stabilized with a resin or wax, and sometimes dyed. It is best suited for jewelry that is not subject to heavy wear, such as pendants and earrings.
Zircon is notably harder and more brilliant than turquoise, with a high refractive index that gives it exceptional sparkle, rivaling that of diamond. Blue zircon's vitreous luster and transparency make it an excellent choice for faceted cuts, allowing light to enter and reflect brilliantly. However, it has poor cleavage, meaning it can split along certain planes if struck with force, requiring careful handling during cutting and setting.
Tanzanite is prized for its unique color and clarity. It is a relatively hard gemstone but possesses perfect cleavage in one direction, making it vulnerable to breakage if impacted. Its most remarkable optical property is pleochroism—the ability to display different colors (blue, violet, and red-violet) when viewed from different angles. Skilled lapidaries orient the stone to showcase the most desirable blue-violet hue. Tanzanite is almost always heat-treated to enhance its color, a process that is stable and accepted within the trade.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, these gemstones are imbued with rich symbolism and metaphysical properties, cherished across cultures for their perceived powers.
Turquoise: Protection and Wisdom Turquoise is universally regarded as a stone of protection, healing, and wisdom. Ancient cultures believed it could ward off evil spirits and protect the wearer from physical harm. It is also associated with clear communication, truth, and emotional balance. In many traditions, turquoise is considered a stone of friendship and loyalty, often exchanged as a token of affection. Its calming blue-green hues are said to promote serenity and inner peace, making it a popular choice for meditation and spiritual practices.
Zircon: Honor and Purity Historically, zircon has been linked to honor, purity, and spiritual growth. It was thought to promote honesty and encourage the wearer to pursue their goals with integrity. Blue zircon, in particular, is associated with clarity of thought and enhanced intuition. Some believe it can help alleviate anxiety and foster a sense of stability and grounding. Its brilliance is often seen as a metaphor for inner light and enlightenment.
Tanzanite: Transformation and Intuition As a modern gemstone, tanzanite has quickly developed its own set of metaphysical associations. It is often called the "stone of transformation," believed to facilitate spiritual awakening and higher consciousness. Its vibrant energy is said to stimulate the throat and third-eye chakras, enhancing communication and intuition. For those born on December 6th, tanzanite symbolizes a journey of self-discovery and personal growth, encouraging introspection and a deeper connection to one's purpose.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of these gemstones, given their distinct physical properties.
Turquoise Care Due to its softness and porosity, turquoise requires gentle handling. It should be cleaned with a soft, damp cloth and mild soap, avoiding harsh chemicals, acids, or ultrasonic cleaners, which can damage or discolor the stone. Store turquoise jewelry separately to prevent scratching by harder gems. Prolonged exposure to sunlight, heat, or cosmetics can also affect its color and stability.
Zircon Care Zircon is relatively durable but can be brittle due to its poor cleavage. It is best cleaned with warm soapy water and a soft brush. Avoid sudden temperature changes and impacts, which can cause fractures. While zircon is resistant to most chemicals, it is advisable to remove jewelry before engaging in activities that might expose it to harsh conditions.
Tanzanite Care Tanzanite's perfect cleavage makes it particularly vulnerable to chipping and breaking. It should never be subjected to ultrasonic or steam cleaning. Instead, clean it with a soft brush, warm water, and mild detergent. It is also sensitive to heat, so keep it away from high temperatures. Due to its cleavage, tanzanite jewelry should be handled with care and stored in a padded box to avoid damage.
Conclusion
The December 6th birthstones—tanzanite, turquoise, and zircon—offer a remarkable blend of history, science, and symbolism. From the ancient protective talisman of turquoise to the billion-year-old legacy of zircon and the modern marvel of tanzanite, each gemstone tells a unique story. Their diverse colors, ranging from sky blue to violet-blue, not only captivate the eye but also carry deep meanings of wisdom, transformation, and protection. For those born on this day, these gemstones provide a meaningful connection to the cosmos and a tangible symbol of their personal journey. Whether chosen for their beauty, their lore, or their rarity, the December 6th trio stands as a testament to the enduring allure of the natural world's most precious creations.