The final month of the year is uniquely distinguished in the world of gemology by not having one, but three official birthstones: Turquoise, Blue Topaz, and Zircon. This multiplicity offers those born in December a rich palette of colors and histories from which to choose. From the ancient, sky-blue talismans of kings to the brilliant, faceted jewels of modern design, the December birthstones represent a fascinating convergence of geological marvel, historical depth, and enduring symbolism. This article explores the distinct characteristics, origins, and lore of these three remarkable gems, providing a comprehensive guide for collectors, enthusiasts, and anyone captivated by their beauty.
A Trio of Gems: History and Modern Adoption
The tradition of assigning a specific gemstone to each month has evolved over centuries, with its most recognizable form originating from the breastplate of Aaron, described in the Old Testament, which featured twelve stones representing the twelve tribes of Israel. The modern list of birthstones, however, was standardized in 1912 by the American National Association of Jewelers (now Jewelers of America) to create a consistent guide for the trade. Turquoise was established as the primary and traditional birthstone for December. Over time, this list has been updated to include alternative stones, providing more choice in color and value. For December, Zircon was added as a secondary stone, and in 1952, Blue Topaz was also officially recognized, solidifying the trio available today. This evolution reflects both historical precedence and the changing availability and popularity of certain gems in the modern market.
Turquoise: The Ancient Sky Stone
Turquoise is arguably the most historically significant of the December stones, with a legacy that spans millennia and continents. Its name is derived from the French phrase pierre turquoise, meaning "Turkish stone," as the gem was first brought to Europe from Turkey via Persian trade routes. However, its origins and use are far older, deeply rooted in ancient civilizations across the globe.
Historical Significance and Lore
Turquoise has been a prized gem for thousands of years. Ancient Egyptians adorned themselves with it, burying it with their dead as a protective charm and a conduit to the afterlife. The famous burial mask of Pharaoh Tutankhamun, discovered in 1922, was heavily inlaid with turquoise, demonstrating its elite status. In Persian culture, Turquoise was a symbol of purity and was believed to ward off unnatural death and ensure a happy life. It was often set into jewelry, crowns, and swords, and was considered a sacred stone.
In the American Southwest, Native American tribes such as the Navajo, Zuni, and Hopi have a profound connection to Turquoise. For them, it is not merely an ornament but a piece of the sky that has fallen to earth. It is used in sacred ceremonies and is believed to offer protection, health, and good fortune. The stone is seen as a living entity, a bridge between the earth and the heavens, and its color is said to change to reflect the well-being of the wearer.
Geological Formation and Sources
Turquoise is a hydrated phosphate of copper and aluminum. Its formation is a rare geological event, occurring in arid regions where acidic, copper-rich groundwater percolates through aluminum-bearing rocks. Over millions of years, this process deposits minerals in cracks and voids, eventually forming the nodules and veins of Turquoise that miners seek. The presence of copper dictates the stone's signature blue-to-green hue, while iron and other trace elements can introduce variations in color.
The quality of Turquoise is heavily dependent on its source. Historic sources include Iran (formerly Persia), which is renowned for producing some of the finest, most uniformly "sky blue" Turquoise with minimal matrix (the host rock inclusions). Other significant sources include the United States (particularly Arizona and New Mexico), Egypt, China, and Afghanistan. American Turquoise is often characterized by its distinctive matrix patterns, such as the "spiderweb" matrix found in stones from the Lander Blue mine.
Gemological Properties
Turquoise is prized for its distinctive color rather than its brilliance. It is an opaque gem with a waxy to vitreous luster. Its hardness on the Mohs scale is relatively low, ranging from 5 to 6, making it somewhat susceptible to scratching and requiring careful handling. This porosity also means it can be sensitive to chemicals, cosmetics, and even skin oils, which can cause discoloration. Due to its relative softness and common inclusions, Turquoise is often stabilized (treated with a clear resin) to enhance its durability and color. This is a standard and accepted industry practice.
| Property | Description |
|---|---|
| Chemical Formula | CuAl₆(PO₄)₄(OH)₈·4H₂O |
| Crystal System | Triclinic |
| Hardness (Mohs) | 5 - 6 |
| Luster | Waxy to Vitreous |
| Transparency | Opaque |
| Color | Sky blue to bluish-green, green |
Blue Topaz: The Modern Luminous Jewel
While Topaz as a mineral has been known since antiquity, Blue Topaz as a popular, widely available gemstone is a distinctly modern phenomenon. Its journey to becoming a mainstream December birthstone is a story of both geological discovery and technological innovation in the gem trade.
From Rare to Abundant: A Historical Shift
Historically, "Topaz" referred to a wide range of yellow stones. The magnificent blue stones popular today were often misidentified as Sapphire or were extremely rare in nature. The transformation began in the 20th century when it was discovered that the abundant, colorless Topaz, primarily mined in Brazil, could be irradiated and heat-treated to produce a stable, vivid blue color. This process made Blue Topaz accessible and affordable for the jewelry market, leading to its official inclusion as a December birthstone in 1952. Its clarity, large crystal sizes, and ability to be precisely cut made it an instant favorite for designers.
Gemological Properties
Blue Topaz is a silicate mineral containing fluorine and hydroxyl ions. It is known for its exceptional clarity and brilliance when cut. With a hardness of 8 on the Mohs scale, it is a durable gemstone suitable for all types of jewelry, including rings and bracelets that are subject to daily wear. The most sought-after shades of Blue Topaz are the deep, saturated "London Blue" and the lighter, sky-like "Swiss Blue." It is important to note that the intense blue color seen in almost all commercial Blue Topaz is the result of treatment; naturally occurring blue Topaz is exceedingly rare and typically very pale.
| Property | Description |
|---|---|
| Chemical Formula | Al₂SiO₄(F,OH)₂ |
| Crystal System | Orthorhombic |
| Hardness (Mohs) | 8 |
| Luster | Vitreous |
| Transparency | Transparent |
| Color | Treated to various shades of blue (Sky, Swiss, London Blue) |
Sources
The primary sources for the colorless Topaz that is treated to become Blue Topaz are Brazil, particularly the states of Minas Gerais and Rio Grande do Sul. Other sources include Nigeria, Madagascar, Pakistan, and Sri Lanka. The treatment process is stable and permanent, making Blue Topaz a reliable and beautiful gem for consumers.
Zircon: The Sparkling Diamond Simulant
Zircon is one of the oldest minerals on Earth, with crystals found in Australia that date back over 4.4 billion years. Despite its age and its status as one of the traditional December birthstones, it is often confused with the man-made cubic zirconia (CZ), a common diamond simulant. This unfortunate name confusion often overshadows Zircon's own remarkable qualities.
A Gem of Fire and Color
Natural Zircon possesses a high refractive index and strong dispersion, giving it a brilliance and "fire" that can rival that of a diamond. Historically, colorless Zircon was widely used as a diamond simulant, and its similarity in appearance to both diamond and CZ has led to persistent confusion. However, Zircon is a natural, valuable gemstone in its own right. While it is available in a variety of colors, the golden-brown to red-brown "Hyacinth" Zircon was the most historically significant. The vibrant blue Zircon popular in modern jewelry is almost always the result of heat treatment, which transforms the original brownish crystals into a desirable pale blue.
Geological Formation and Sources
Zircon is a zirconium silicate and is found as a minor mineral in many igneous and metamorphic rocks. It is highly resistant to weathering and is often found in stream sediments as detrital grains. Gem-quality Zircon, however, is found in specific deposits. The main sources for Zircon today are Cambodia, Sri Lanka, and Thailand. Australia also has significant deposits, particularly in the Murray Basin, which produce the gem in a range of colors.
Gemological Properties
Zircon is a hard and dense gem, with a hardness of 6.5 to 7.5 on the Mohs scale. However, it is also known for its brittleness and perfect cleavage in two directions, meaning it can be easily chipped or broken if struck with sufficient force. This property requires jewelers to handle it with care during setting and consumers to be mindful when wearing it in rings. Its high refractive index (1.92-1.98) is responsible for its exceptional brilliance.
| Property | Description |
|---|---|
| Chemical Formula | ZrSiO₄ |
| Crystal System | Tetragonal |
| Hardness (Mohs) | 6.5 - 7.5 |
| Luster | Adamantine to Vitreous |
| Transparency | Transparent to Opaque |
| Cleavage | Perfect |
| Color | Blue, golden-brown, yellow, green, red (heat treatment common for blue) |
Symbolism and Metaphysical Beliefs
The December birthstones are rich in symbolic meaning, carrying forward ancient beliefs into modern times.
- Turquoise is universally regarded as a stone of protection, wisdom, and good fortune. It is believed to attract positive energy, calm the mind, and promote spiritual grounding. Its connection to the sky and water makes it a symbol of tranquility and peace.
- Blue Topaz is associated with calm, clarity, and communication. It is often called the "Stone of Truth" and is believed to aid in honest self-expression and emotional balance. Its cool blue hues are thought to have a soothing effect on the wearer.
- Zircon is believed to promote honor, purity, and spiritual growth. It is said to help one overcome negative feelings and find peace and prosperity. Its brilliant sparkle is thought to inspire diligence and boost self-esteem.
Care and Cleaning
Proper care is essential to maintain the beauty of these gems, and the approach varies significantly due to their different physical properties.
- Turquoise: Due to its porosity and low hardness, Turquoise requires gentle care. Clean it with warm water, a mild soap, and a soft cloth. Avoid ultrasonic cleaners, steamers, and harsh chemicals, which can damage or discolor the stone. Store it away from other jewelry to prevent scratching.
- Blue Topaz: As a durable gem, Topaz is relatively easy to care for. It can be cleaned with warm, soapy water and a soft brush. While it is tough, it can be chipped by hard blows due to its perfect cleavage, so caution is advised.
- Zircon: Despite its hardness, Zircon's brittleness and cleavage make it susceptible to damage from impacts and rapid temperature changes. It should not be cleaned in an ultrasonic cleaner. The safest method is warm, soapy water and a soft brush, with careful handling.
Conclusion
The birthstones of December—Turquoise, Blue Topaz, and Zircon—offer a compelling narrative of geological diversity, historical depth, and cultural significance. From the ancient, protective talisman of Turquoise to the modern, brilliant sparkle of Zircon and the serene clarity of Blue Topaz, each gem provides a unique expression for those born in the final month of the year. Together, they form a trio that spans the full spectrum from opaque and earthy to transparent and luminous, embodying both the wisdom of the past and the innovations of the present. Their enduring appeal lies in this rich combination of beauty, durability, and the timeless stories they carry.