The final month of the year is associated with not one, but three distinct and captivating birthstones: Turquoise, Zircon, and Tanzanite. Each gem possesses a unique history, a signature color, and a set of properties that make it a cherished December birthstone. This trio offers a remarkable spectrum of hues, from the iconic sky blue of Turquoise to the fiery brilliance of Zircon and the vivid violet-blue of Tanzanite. The selection of these three gemstones provides those born in December with a rich palette of options, each carrying its own symbolism and geological story. The significance of these stones is deeply rooted in ancient beliefs of good fortune and protection, and their journey to becoming modern birthstones is a testament to their enduring appeal.
The exploration of these gemstones will cover their historical origins and the lore that surrounds them. We will delve into the geological processes that create these treasures and the specific locations around the world where they are mined. A detailed examination of their gemological properties, including color, hardness, and chemical composition, will provide a scientific understanding of what makes each stone unique. Furthermore, we will discuss the metaphysical beliefs associated with the December birthstones and offer practical advice on their care and maintenance to ensure their lasting beauty. By examining these three gems, we gain a comprehensive appreciation for the natural artistry and cultural importance of December's birthstones.
History and Lore
The history of December's birthstones is as diverse as the gems themselves, with stories spanning ancient civilizations and modern discoveries. Turquoise is the most ancient of the three, with a legacy of use and reverence that dates back millennia. Its name is derived from the French phrase "pierre tourques," or "Turkish stone," reflecting its introduction to Europe from the mines of Persia via Turkey. Long before its journey west, Turquoise was a sacred stone to many cultures. It was highly prized in ancient Egypt, where it was used to create intricate jewelry and funerary objects for pharaohs. The Persians believed it offered protection from unnatural death and that its color would change to warn the wearer of impending danger. Similarly, in ancient Tibet, Turquoise was valued not just for its beauty but for its spiritual significance, used extensively in ceremonial objects and personal adornment.
Across the Atlantic, Native American tribes, particularly in the American Southwest, have a profound connection to Turquoise. For these cultures, the stone is not merely a gem but a piece of the sky that has fallen to earth, a living entity that connects the wearer to the heavens and the earth. It has been used in sacred ceremonies, as a talisman for protection, and as a symbol of wealth and status. The stone's association with good fortune and protection has been a consistent thread throughout its long history, making it a cornerstone of December's birthstone tradition.
Zircon, while also an ancient gem, has a history that is often confused due to the similarity of its name with the synthetic cubic zirconia. However, natural Zircon is one of the oldest minerals on Earth, with some specimens dating back billions of years. For centuries, Zircon was a key component of the "four C's" of gemstones, alongside Diamond, Ruby, and Sapphire. In the Middle Ages, Zircon was believed to promote honor and prosperity in its wearer and to bring sleep. It was also thought to ward off evil spirits and protect travelers, making it a popular talisman. The most prized variety of Zircon is the blue, which has been a popular gem for centuries. Its exceptional brilliance and fire, which can rival that of a diamond, have made it a favorite in jewelry throughout history, particularly in the Victorian era.
Tanzanite is the newcomer of the group, a modern discovery that has rapidly gained global popularity. Its story begins in the Merelani Hills of Tanzania in 1967, where it was discovered by a Tanzanian prospector named Manuel d'Souza. Initially, the blue-violet crystals were mistaken for another mineral, but their unique color soon revealed their true identity as a variety of zoisite. The gem was named "Tanzanite" by Tiffany & Co., which recognized its potential and began promoting it heavily in the 1960s. The company marketed it as "the most beautiful blue gem to be discovered in 2,000 years," and its rarity, being found in only one location in the world, added to its allure. Despite its recent origin, Tanzanite has quickly become a significant player in the gemstone market and was officially added to the modern list of birthstones for December in 2002, recognizing its importance and desirability.
Geological Formation and Sources
The formation of these three gemstones occurs under vastly different geological conditions, leading to their unique characteristics and rarity. Turquoise is a secondary mineral that forms in arid or semi-arid regions where acidic, copper-rich water percolates through rocks containing aluminum and phosphorus. This process occurs near the Earth's surface, and the resulting nodules or veins are typically found in areas where these conditions have persisted for millions of years. The most significant historical source of Turquoise is the Nishapur district of Iran, which produced the stone for thousands of years and is still known for producing high-quality material with a desirable "spiderweb" matrix. Another major source is the Southwestern United States, particularly in states like Arizona, New Mexico, and Nevada. These American mines produce a wide range of colors and matrix patterns, with stones from the Sleeping Beauty mine known for their pure, sky-blue color without matrix. Other notable sources include China and Egypt.
Zircon is a mineral that forms within igneous and metamorphic rocks. It is a primary mineral found in magma that cools to form granite and other plutonic rocks. It is also formed during metamorphism when sedimentary rocks are subjected to intense heat and pressure. Because it is extremely resistant to weathering, zircon crystals can survive for billions of years and are often found in sedimentary deposits, such as riverbeds and beaches. The primary sources for gem-quality Zircon are found in Southeast Asia and Africa. Thailand and Cambodia are renowned for producing the high-quality blue Zircon that is most popular in jewelry. Other sources include Sri Lanka, which produces a variety of colors, and Australia, which is known for its brown Zircons that can be heat-treated to achieve a blue color.
Tanzanite's geological origin is exceptionally rare. It is a variety of the mineral zoisite and is found exclusively in a small, four-square-kilometer area in the Merelani Hills of Northern Tanzania, near the base of Mount Kilimanjaro. This specific geological setting is unique for the conditions that allowed for the formation of this gem. The process is believed to have occurred when tectonic plate shifts and intense heat and pressure altered the parent rock, causing the presence of vanadium to create the gem's signature blue-violet color. The fact that Tanzanite is found in only one location on the planet makes it thousands of times rarer than Diamond. This geographic limitation also means that the supply is finite, adding to its value and mystique.
Gemological Properties
Understanding the gemological properties of each stone is crucial for appreciating its value, durability, and suitability for jewelry. While they share the status of December's birthstone, their physical and chemical characteristics are quite different.
Turquoise is an opaque mineral with a chemical composition of a hydrated phosphate of copper and aluminum. Its color ranges from blue to green, with the most valued shade being a pure, "robin's egg" blue. The presence of copper determines the blueness, while iron contributes to the greenish tones. Turquoise is relatively soft, with a Mohs hardness of 5 to 6, making it susceptible to scratches and chemicals. It often contains a matrix, which is the remnants of the host rock, creating intricate web-like patterns that can be highly desirable. Due to its porosity, Turquoise is frequently stabilized with wax or resin to enhance its durability and color.
Zircon is a mineral with a chemical composition of zirconium silicate. It is known for its exceptional brilliance and fire, which are among the highest of any natural gemstone. Zircon has a high refractive index and strong dispersion, properties that contribute to its dazzling sparkle. It is relatively hard, with a Mohs hardness of 6.5 to 7.5, but it is also brittle and can be easily chipped or abraded if not handled with care. Zircon occurs in a wide variety of colors, including blue, yellow, orange, brown, and red. The blue variety, which is the most popular for December, is typically created by heat-treating brown Zircon crystals at high temperatures. Zircon is also pleochroic, meaning it can show different colors when viewed from different crystal directions.
Tanzanite is a variety of zoisite and has a chemical composition of calcium aluminum hydroxyl cyclosilicate, with vanadium as a color-causing agent. It is known for its strong trichroism, a property that causes it to display three different colors—blue, violet, and burgundy—when viewed from different angles. Gem cutters must orient the crystal carefully to showcase the dominant blue-violet hue. Tanzanite's Mohs hardness is 6.5 to 7, making it suitable for jewelry, but it requires care to avoid scratches and impacts. Its color is its most defining feature, ranging from a light lavender to a deep, saturated violet-blue. The most valuable stones are those with a deep, pure violet-blue color.
Summary of Gemological Properties
| Gemstone | Chemical Composition | Mohs Hardness | Key Properties |
|---|---|---|---|
| Turquoise | Hydrated phosphate of copper and aluminum | 5 - 6 | Opaque, often contains a matrix, color from blue to green. |
| Zircon | Zirconium silicate | 6.5 - 7.5 | High brilliance and fire, brittle, pleochroic, wide color range. |
| Tanzanite | Calcium aluminum hydroxyl cyclosilicate | 6.5 - 7 | Strong trichroism (blue, violet, burgundy), sensitive to heat. |
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, the December birthstones are imbued with a rich tapestry of symbolism and metaphysical beliefs that have been passed down through generations. These beliefs contribute to the stones' significance as personal talismans and meaningful gifts.
Turquoise is perhaps the most famous of the three for its protective qualities. Across numerous cultures, it has been regarded as a stone of healing, good fortune, and spiritual grounding. It is often called the "Master Healer" and is believed to align all the chakras, stabilizing mood swings and instilling inner calm. Its connection to the sky and water elements makes it a symbol of wisdom, tranquility, and protection during travel. Many believe that Turquoise can absorb negative energies and protect the wearer from harm, making it a powerful amulet for warriors, shamans, and travelers alike.
Zircon is also associated with protection and prosperity. It is believed to promote honor and purity in its wearer. In some traditions, Zircon is said to help with spiritual grounding and to bring wisdom and wealth. The blue Zircon, in particular, is associated with clarity of thought and peace of mind. It is thought to aid in overcoming challenges and to inspire a sense of self-confidence and discipline. For those born in December, wearing Zircon is said to enhance their natural traits of ambition and perseverance.
As a modern gem, Tanzanite has quickly accumulated its own set of metaphysical associations. It is often called the "Stone of Transformation" and is believed to facilitate a higher consciousness, intuition, and spiritual perception. Its energy is thought to be calming and uplifting, helping to alleviate stress and depression. Many crystal healers use Tanzanite to open the throat and crown chakras, promoting clear communication and a connection to higher realms. It is also associated with uniqueness and individuality, reflecting its singular point of origin. For those seeking to make significant life changes, Tanzanite is believed to provide the courage and insight needed to move forward.
Care and Cleaning
Proper care is essential to maintain the beauty and integrity of any gemstone, and the December birthstones each have specific requirements due to their unique physical properties.
Turquoise, with its relatively low hardness and porosity, requires the most careful handling. It is susceptible to scratches from harder materials and can be damaged by chemicals, cosmetics, and even the natural oils of the skin, which can cause discoloration over time. To clean Turquoise, use only warm, soapy water and a soft brush. Avoid ultrasonic cleaners, steam cleaners, and harsh detergents. It is best to store Turquoise jewelry separately in a soft cloth to prevent it from being scratched by other gems. Regular, gentle cleaning will help preserve its vibrant color.
Zircon is a relatively hard gem but is also brittle. This means it can be chipped or abraded if knocked against a hard surface, so it is best set in protective settings like bezels for rings that are worn daily. Cleaning Zircon is straightforward; it can be washed with warm, soapy water and a soft brush. It is also generally safe to use an ultrasonic cleaner, but caution is advised for stones that may have fractures. Avoid exposing Zircon to sudden extreme temperature changes, as this can cause the stone to crack.
Tanzanite has a hardness of 6.5 to 7, making it durable enough for most jewelry, but it is still susceptible to scratching and chipping. It is also sensitive to heat, which can alter its color. Therefore, it is crucial to keep Tanzanite away from high temperatures and direct sunlight for prolonged periods. Cleaning should be done with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaners, as the vibrations and heat can damage the stone. When not being worn, store Tanzanite jewelry in a soft, padded box to protect it from damage.
Conclusion
The birthstones of December—Turquoise, Zircon, and Tanzanite—offer a compelling trio of gems that are as diverse in their origins and properties as they are unified in their symbolic meaning. From the ancient, protective power of Turquoise to the brilliant fire of Zircon and the transformative energy of Tanzanite, each stone provides a unique connection to the natural world and human history. Their stories take us from the arid mines of Persia and the American Southwest to the alluvial deposits of Southeast Asia and the single, precious location of the Merelani Hills in Tanzania. The gemological properties of each, from Turquoise's opaque beauty to Zircon's unmatched brilliance and Tanzanite's captivating trichroism, provide a fascinating study in mineralogy. For those born in December, these birthstones are more than just beautiful adornments; they are symbols of good fortune, protection, and transformation, carrying with them a legacy of lore and a promise of enduring beauty.