December is a month of contrasts, marked by the deepening chill of winter and the warm glow of holiday celebrations. For those born in this final month of the year, the birthstone selection is uniquely abundant. Unlike most months, which are associated with a single gem, December boasts four distinct and captivating birthstones: Turquoise, Tanzanite, Blue Zircon, and Blue Topaz. This diversity offers a remarkable range of colors, histories, and symbolic meanings, allowing December-born individuals to choose a stone that resonates with their personal style and story. Each gemstone in this quartet carries its own legacy, from ancient amulets believed to ward off danger to modern marvels discovered in the 20th century. This guide delves into the geological origins, gemological properties, historical lore, and cultural significance of these four radiant stones, providing a comprehensive resource for gemstone enthusiasts, jewelry buyers, and students of gemology.
The existence of four official birthstones for December is a relatively modern development, driven by consumer demand and the expansion of the global gemstone market. Historically, the month was associated with fewer gems, but over time, new discoveries and increased availability led to the expansion of the list. The traditional birthstones for December are Turquoise and Zircon, with Tanzanite and Blue Topaz joining the ranks as modern additions. The Gemological Institute of America (GIA) lists Turquoise, Tanzanite, and Zircon as December’s birthstones, noting their varied blue-to-green and violet hues. Blue Topaz, while not always listed in historical lists, has gained significant popularity and is now frequently treated as a mainstream December birthstone, particularly in the United States. This expansion offers consumers more flexibility in terms of price, durability, and style, ensuring that every December birthday can be celebrated with a gemstone that is both beautiful and meaningful.
History and Lore: From Ancient Amulets to Modern Discoveries
The concept of birthstones can be traced back to ancient civilizations, including ancient Egypt, Greece, and Rome, where gemstones were believed to possess mystical and healing properties. The association of specific stones with specific months evolved over centuries, culminating in the standardized lists we recognize today. For December, the historical narrative is particularly rich, spanning from the ancient world to the present day.
Turquoise stands as the oldest of the December birthstones, with a history that stretches back millennia. Its name is derived from the French word pierre tourques, or "Turkish stone," as the gem was first brought to Europe from the mines of Persia (modern-day Iran) and the Sinai Peninsula through Turkish gem markets. From the earliest times, turquoise was a favored gem for amulets, prized for its relatively soft nature, which made it easy to cut into various shapes and inscribe with protective symbols. It was considered a stone of protection against danger and misfortune and was believed to bring good fortune to its wearer. Turquoise was especially cherished by lovers and married couples, who believed it protected their relationships and preserved friendship if given as a gift. A unique property attributed to turquoise was its ability to warn its wearer of approaching illness or danger by changing color, becoming pale. This lore was widespread; Tibetans considered turquoise a birthstone of fortune, health, and success, and the gem was so valued that it was often used as currency. In the Americas, ancient Incas and Mayas offered turquoise as a gift to their gods, while Native Americans of the Southwest associated the stone with youth and strength.
Zircon, another traditional December stone, has a long and storied history, though its name is often confused with the synthetic cubic zirconia. For centuries, zircon was highly valued for its exceptional brilliance and fire, which can rival that of a diamond. Its name is believed to be derived from the Persian word zargun, meaning "gold-colored," though its most prized color is a vivid blue. Blue zircon, in particular, was cherished for its dazzling sparkle and was often mistaken for diamond due to its high refractive index. The gem’s history is intertwined with trade and travel, as it was found in various locations and valued across different cultures for its beauty and perceived mystical properties.
Tanzanite is the newest of the four, a relative newcomer to the gemological world. Discovered in the 20th century, this gem is celebrated for its mesmerizing, vibrant blue hue, which ranges from a light, ultramarine blue to a deep, violet-blue. Its discovery was a significant event in the gem trade, introducing a new and unique gemstone to the market. While its history is brief compared to turquoise and zircon, it has quickly become a symbol of modern luxury and sophistication, prized for its rarity and intense color.
Blue Topaz has also gained prominence as a modern birthstone for December. The name "Topaz" originates from the Greek word Topazios, which was the ancient name of an island in the Red Sea. However, it was later discovered that the stones mined on this island were actually peridot, not topaz. Despite this, the name stuck. Blue topaz is known for its vivid sky-blue hues and striking brilliance, offering a spectrum of blue shades from pale, almost translucent tones to rich, vibrant aqua. Its popularity in modern jewelry, especially in the United States, has solidified its place as a mainstream December birthstone.
Geological Formation and Sources
Each of the four December birthstones forms under distinct geological conditions and is mined from specific regions of the world, contributing to their rarity and value.
Turquoise is a secondary mineral that forms in the near-surface environment where water-rich solutions interact with rocks containing copper, aluminum, and phosphorus. It is typically found in arid regions where these conditions are met. Historically, the most significant sources were in Persia (Iran) and the Sinai Peninsula. Today, major sources include the United States (particularly Arizona, New Mexico, and Nevada), China, and other regions. The gem's formation is often associated with copper deposits, and its color can vary from sky blue to greenish blue, depending on the presence of iron or other impurities.
Zircon is a mineral that forms in igneous and metamorphic rocks. It is a common accessory mineral in many rock types, but gem-quality zircon is rarer. The most prized blue zircon is often sourced from Cambodia, Sri Lanka, and Thailand. The gem's formation requires specific conditions of high temperature and pressure, and it is often found in placer deposits (gravels) where weathering has concentrated the durable crystals.
Tanzanite is found in only one location in the world: the Merelani Hills of northern Tanzania, near the base of Mount Kilimanjaro. This geographic exclusivity makes it one of the rarest gemstones on Earth. It forms under specific geological conditions where the mineral zoisite is exposed to heat and pressure, which causes the formation of vanadium, giving the stone its characteristic blue-violet color. The gem is typically found in alluvial deposits and in the host rock, which is mined for the crystals.
Blue Topaz is a variety of the mineral topaz, which forms in pegmatites and high-temperature veins. Natural blue topaz is quite rare; most of the vivid blue topaz on the market is the result of treating colorless or pale blue topaz with radiation and heat. Major sources of topaz include Brazil, Nigeria, and Sri Lanka. The treatment process is a standard industry practice and is disclosed to consumers, making blue topaz an affordable and accessible gemstone for jewelry.
Gemological Properties
The gemological properties of these stones vary significantly, influencing their durability, care, and suitability for different types of jewelry. The following table summarizes the key properties based on standard gemological references, as the provided sources do not offer detailed scientific data. However, the general characteristics are well-established in gemology.
| Gemstone | Chemical Composition | Mohs Hardness | Crystal System | Common Treatments | Notable Properties |
|---|---|---|---|---|---|
| Turquoise | Hydrated copper aluminum phosphate | 5 - 6 | Triclinic | Stabilization (waxing/resin) | Porous, can change color with exposure to chemicals, lotions, and sweat. |
| Zircon | Zirconium silicate (ZrSiO₄) | 6.5 - 7.5 | Tetragonal | Heat treatment (for blue color) | High refractive index and strong dispersion ("fire"). |
| Tanzanite | Calcium aluminum hydroxyl silicate (Zoisite) | 6.5 - 7 | Orthorhombic | Heat treatment (to enhance blue color) | Pleochroic (shows different colors from different angles). |
| Blue Topaz | Aluminum fluoride silicate (Al₂SiO₄(F,OH)₂) | 8 | Orthorhombic | Radiation and heat treatment | Durable, but treatment is standard for blue color. |
Turquoise has a relatively low hardness (5-6 on the Mohs scale), making it susceptible to scratching and damage. It is also porous, which means it can absorb oils, chemicals, and lotions, potentially leading to discoloration. For this reason, turquoise is often stabilized with wax or resin to improve its durability and color retention. It is not recommended for daily wear in rings or bracelets that are exposed to hard surfaces or chemicals.
Zircon is considerably harder and more durable, with a Mohs hardness of 6.5 to 7.5. This makes it suitable for a variety of jewelry, including rings. However, it can be brittle and prone to chipping if struck hard. The brilliant sparkle of zircon is due to its high refractive index and strong dispersion, which gives it a fire that can exceed that of diamond.
Tanzanite has a hardness of 6.5 to 7, making it relatively durable for jewelry. However, it is important to note that tanzanite is often treated with heat to achieve its vibrant blue color. This treatment is stable and permanent. A key characteristic of tanzanite is its strong pleochroism; it can show different shades of blue and violet from different angles, which gem cutters must consider to maximize its color in the finished stone.
Blue Topaz is one of the hardest and most durable of the four, with a Mohs hardness of 8. This makes it an excellent choice for all types of jewelry, including rings and bracelets that are subject to daily wear. The blue color in most topaz is not natural but is achieved through treatment. This process involves exposing colorless or pale blue topaz to radiation, which creates the deep blue color, followed by heating to stabilize it. This treatment is widely accepted and disclosed, and it allows for the production of large, vividly colored gems at an affordable price point.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, each of the December birthstones carries a rich tapestry of symbolic meanings and metaphysical beliefs, many of which have persisted for centuries.
Turquoise is universally regarded as a stone of protection, healing, and good fortune. Its lore is deeply rooted in its ability to safeguard the wearer. It was believed to warn of impending danger by changing color, to protect against falls and accidents, and to bring health and prosperity. In relationships, it symbolized loyalty, trust, and enduring love, making it a popular gift between partners and friends. For Tibetans, it was a stone of fortune, health, and success, integral to their culture and economy.
Zircon has been associated with wisdom, honor, and wealth. Its diamond-like brilliance led to beliefs that it could enhance clarity of thought and bring spiritual insight. In some traditions, it was considered a stone of prosperity and was worn to attract abundance and success.
Tanzanite, as a modern discovery, has quickly accumulated its own set of symbolic meanings. It is often associated with transformation, intuition, and spiritual awakening. Its unique blue-violet color is said to stimulate the higher mind and promote a sense of calm and clarity. It is considered a stone of vision and understanding, helping the wearer to connect with their higher self.
Blue Topaz is symbolically linked to communication, truth, and clarity. Its serene blue color is believed to have a calming effect, promoting peacefulness and reducing stress and anxiety. It is also associated with creativity and self-expression, making it a favored stone for those who seek to articulate their thoughts and feelings more effectively.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of these gemstones. The recommended care methods are directly tied to their gemological properties.
Turquoise requires the most careful handling. It should be protected from prolonged exposure to water, chemicals, lotions, perfumes, and extreme temperatures, as these can cause discoloration or damage to the stabilization material. Cleaning should be done with a soft, dry cloth. Avoid ultrasonic cleaners and steam cleaners, which can be too harsh. It is best to put on turquoise jewelry after applying cosmetics and to remove it before household chores or swimming.
Zircon is relatively hard but can be brittle. It should be protected from sharp blows and rough handling. To clean, use warm water, mild soap, and a soft brush. Avoid sudden temperature changes, as zircon can be damaged by thermal shock. Ultrasonic cleaners are generally safe for zircon, but it is always best to check with a professional jeweler, especially if the stone has fractures or inclusions.
Tanzanite should be handled with care due to its relative softness and cleavage. It is not recommended for rings worn daily, as it can be prone to scratching and chipping. Cleaning can be done with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaners, as the vibrations and heat can cause damage. It is also advisable to store tanzanite jewelry separately to prevent it from being scratched by harder stones.
Blue Topaz is the most durable of the four and is relatively easy to care for. It can be cleaned with warm, soapy water and a soft brush. Ultrasonic cleaners are generally safe for untreated or heat-treated topaz, but caution is advised for stones that may have fractures. As with all gemstones, it is best to avoid harsh chemicals and sudden temperature changes.
Conclusion
The four birthstones of December—Turquoise, Tanzanite, Blue Zircon, and Blue Topaz—offer a remarkable diversity that reflects the multifaceted nature of the month itself. From the ancient, protective amulet of Turquoise to the modern, transformative allure of Tanzanite, each stone provides a unique connection to history, geology, and personal symbolism. The expansion of the December birthstone list is a testament to the evolving world of gemology and consumer preference, providing options that cater to a wide range of tastes, budgets, and lifestyles. Whether one is drawn to the earthy heritage of turquoise, the brilliant fire of zircon, the rare violet-blue of tanzanite, or the durable, sky-blue clarity of topaz, each gemstone serves as a meaningful and beautiful emblem for those born in the year's final month. Understanding their origins, properties, and care ensures that these radiant stones can be cherished for generations to come.