December, the final month of the year, is not only a time for celebration and reflection but also a month rich in gemological significance. For those born in December, the month offers a unique distinction: four officially recognized birthstones—Turquoise, Tanzanite, Blue Zircon, and Blue Topaz—each with its own captivating color, history, and symbolism. This collection of blue-hued gems spans from ancient treasures to modern marvels, reflecting both the natural world and the cultural imagination.
This article delves into the world of December birthstones, examining their geological origins, historical significance, gemological properties, and modern relevance. Each stone carries a distinct story, from the ancient traditions surrounding Turquoise to the relatively recent discovery of Tanzanite. Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, this guide offers a comprehensive look at the birthstones of December.
History and Lore
The tradition of assigning gemstones to months of the year has its roots in ancient cultures, where certain stones were believed to possess protective or healing powers. The earliest records of birthstones can be traced back to the breastplate of the High Priest Aaron in the Bible and the foundation of New Jerusalem as described in the Book of Revelation. These ancient lists served as the foundation for modern birthstone traditions, which evolved over centuries and were later formalized in the 20th century by organizations such as the American National Association of Jewelers and the International Gem Society.
For December, the birthstone tradition has expanded over time. While Turquoise has been the traditional December birthstone for centuries, the 20th and 21st centuries have seen the addition of Tanzanite, Blue Zircon, and Blue Topaz. This expansion reflects not only the growing appreciation for blue gemstones but also the desire to provide a wider range of options for jewelry design and personal expression.
Turquoise: The Ancient Treasure
Turquoise is one of the oldest known gemstones, with a history that spans thousands of years and continents. Its use dates back to Ancient Egypt, where it was prized for its deep blue-green color and was often used in amulets and jewelry for pharaohs and royalty. The stone was believed to offer protection, wisdom, and good fortune, and it was also used in religious rituals and funerary practices.
In the American Southwest, Native American cultures have long revered turquoise for its spiritual significance. It was often used in ceremonial regalia and was believed to connect the earth and sky. Some traditions suggest that turquoise could change color or crack in response to danger, serving as a warning to the wearer. These beliefs have persisted through the centuries and continue to influence modern interpretations of the stone's properties.
The name "turquoise" comes from the French phrase "pierre turquoise", meaning "Turkish stone," as the gem was introduced to Europe via the Ottoman Empire. However, the stone was originally mined in Persia (modern-day Iran) and later in the American Southwest and Mideast.
Tanzanite: The Modern Marvel
In contrast to the ancient origins of Turquoise, Tanzanite is a relatively new discovery in the world of gemology. Found in 1967 in the foothills of Mount Kilimanjaro in Tanzania, Tanzanite was first identified as a violet-colored form of columbite. It was later reclassified as a type of zircon, but its unique color and properties set it apart from other zircons.
Tanzanite is notable for its trichroism, a property that allows it to appear in different colors—typically blue, violet, and brown—depending on the angle of light. This effect gives the stone a dynamic and captivating appearance, especially under natural daylight. Its discovery was a significant event in the gemstone world, as it was the first new gemstone to be discovered in the 20th century and the only gemstone found in a single country—Tanzania.
Tanzanite quickly gained popularity and was officially designated as a December birthstone in the 1980s. Its association with the month of December reflects its cool, serene color and its symbolic connection to clarity, creativity, and emotional balance.
Blue Zircon and Blue Topaz: Versatile Additions
Blue Zircon and Blue Topaz were added to the December birthstone list in the 20th century, offering more options for jewelry design and personal preference. While both stones are blue, they differ significantly in terms of their formation, hardness, and visual properties.
Blue Zircon, a type of zircon that has been heat-treated to enhance its blue color, is known for its sparkling brilliance and high refractive index. It was once confused with diamonds and cubic zirconia due to its fire and luster. Blue Zircon is a relatively affordable gemstone that offers a luxurious appearance, making it a popular choice for rings, earrings, and pendants.
Blue Topaz, on the other hand, is a naturally occurring gemstone that has been enhanced through irradiation and heat treatment to produce its characteristic blue color. It is one of the hardest December birthstones, with a Mohs hardness of 8, making it highly durable and suitable for everyday wear. Blue Topaz is also one of the most affordable December birthstones, which has contributed to its popularity in modern jewelry design.
Together, these four gemstones form a diverse and beautiful collection that reflects both ancient traditions and modern innovation.
Geological Formation and Sources
Each of the four December birthstones has a unique geological origin and source, shaped by the natural processes of the Earth. Understanding how these gemstones are formed and where they are found can provide valuable insight into their rarity, availability, and care requirements.
Turquoise: The Product of Copper and Time
Turquoise is an opaque, phosphate mineral that forms in the weathering zone of copper deposits. It is typically found in cavities and veins within limestone and volcanic rock, where it is formed by the reaction of copper-rich groundwater with other minerals such as aluminum, phosphorus, and hydrogen.
The blue and green colors of turquoise are due to the presence of copper, while the brown, black, or gray matrix patterns that run through the stone are caused by the surrounding rock. These matrix patterns make each piece of turquoise unique, with some stones displaying a fine, web-like network and others having more pronounced, linear patterns.
The most significant sources of turquoise are found in the American Southwest, particularly in Arizona, New Mexico, and Nevada, as well as in Iran, China, and Egypt. The quality and color of turquoise can vary depending on the mineral content and environmental conditions of the deposit, with the Persian and Southwestern U.S. turquoise being especially prized for their rich blue color and minimal matrix.
Tanzanite: The One-of-a-Kind Gem
Tanzanite is a trigonal mineral composed primarily of zirconium silicate. It is only found in Tanzania, where it occurs in metamorphic rock formations near the base of Mount Kilimanjaro. The region's unique geological history, involving the collision of tectonic plates and the presence of rare minerals, has created the conditions necessary for tanzanite to form.
Tanzanite is typically mined in the Merelani Hills, where it is extracted from pegmatite deposits. These deposits are rich in zirconium, which is the primary element responsible for the stone's color. The violet-blue color of tanzanite is due to the presence of trivalent vanadium, and the stone must be heat-treated to stabilize and enhance its color.
Given that Tanzanite is only found in Tanzania, it is a rare and valuable gemstone. The limited supply and increasing demand have led to concerns about the future availability of the stone, making it a collectible gem with long-term value.
Blue Zircon: The Sparkling Surprise
Blue Zircon is a type of zircon that has been heat-treated to develop its blue color. Zircon is a zirconium silicate mineral that occurs in a wide range of colors, including brown, yellow, orange, red, and green, but it is the blue variety that is most commonly associated with December birthstones.
Zircon forms in igneous rocks, particularly granite and basalt, and is often found in alluvial deposits where it has been eroded and transported by water. The blue color of zircon is the result of irradiation and heat treatment, which alters the crystal structure and enhances the gem's color. This process is stable and does not affect the stone's durability.
Significant sources of zircon include Australia, Thailand, Cambodia, and Brazil. The blue zircon used in jewelry is primarily sourced from Australia and Cambodia, where it is mined and then treated to develop its vibrant blue hue.
Blue Topaz: The Affordable Elegance
Blue Topaz is a silicate mineral composed of aluminum and fluorine, and it is one of the hardest December birthstones, with a Mohs hardness of 8. It occurs naturally in a yellowish-brown color, but it is commonly irradiated and heat-treated to enhance its blue color, which can range from sky blue to deep London blue.
Topaz is typically found in granite and rhyolite deposits, and it is often associated with pegmatite and metamorphic rocks. It is mined in a variety of locations around the world, including Brazil, Mexico, Pakistan, and the United States. The Brazilian deposits are particularly well-known for producing high-quality topaz, including the blue topaz used in jewelry.
The durability and affordability of blue topaz make it a popular choice for everyday jewelry, and its brilliant color and clarity give it a luxurious appearance that rivals more expensive gemstones.
Gemological Properties
Each of the December birthstones has distinct gemological properties that define its appearance, durability, and care requirements. These properties are important for both gemologists and jewelry buyers, as they influence how the stones are used in jewelry and how they should be maintained.
Turquoise: Soft and Unique
| Property | Description |
|---|---|
| Color | Blue to green, often with brown or black matrix patterns |
| Hardness | 5–6 on the Mohs scale |
| Luster | Waxy to dull |
| Transparency | Opaque |
| Chemical Composition | Hydrated phosphate of aluminum and copper |
| Refractive Index | 1.61–1.65 |
Turquoise is a relatively soft gemstone, which makes it susceptible to scratching, cracking, and discoloration. It is also porous, meaning it can absorb oils, lotions, and cleaning agents, which can affect its color and surface. For this reason, turquoise should be handled with care and stored separately from harder gemstones to prevent scratches.
Tanzanite: Trichromatic and Sensitive
| Property | Description |
|---|---|
| Color | Blue to violet, often with brown undertones |
| Hardness | 6–7 on the Mohs scale |
| Luster | Vitreous |
| Transparency | Translucent to opaque |
| Chemical Composition | Zirconium silicate with vanadium impurities |
| Refractive Index | 1.69–1.70 |
Tanzanite is known for its trichroism, which means it can display three different colors depending on the angle of light. It is also sensitive to sudden temperature changes, so it should not be exposed to extreme heat or cold. Tanzanite is also sensitive to UV light, which can cause fading over time. For these reasons, it is best to store tanzanite in a cool, dark place and to avoid exposing it to direct sunlight for prolonged periods.
Blue Zircon: Sparkling and Durable
| Property | Description |
|---|---|
| Color | Blue to violet |
| Hardness | 6–7.5 on the Mohs scale |
| Luster | Vitreous |
| Transparency | Transparent to translucent |
| Chemical Composition | Zirconium silicate |
| Refractive Index | 1.90–2.00 |
Blue Zircon is known for its high refractive index, which gives it a sparkling brilliance similar to diamonds. It is also relatively durable, making it suitable for everyday wear. However, like all zircons, it has a high dispersion, which can create a fire-like effect when light passes through it. Blue Zircon is also sensitive to heat, so it should not be exposed to high temperatures, such as those used in ultrasonic cleaners or steam cleaners.
Blue Topaz: Hard and Affordable
| Property | Description |
|---|---|
| Color | Blue (sky blue to London blue) |
| Hardness | 8 on the Mohs scale |
| Luster | Vitreous |
| Transparency | Transparent |
| Chemical Composition | Aluminum silicate with fluorine |
| Refractive Index | 1.61–1.64 |
Blue Topaz is one of the hardest December birthstones, with a Mohs hardness of 8, making it highly durable and suitable for everyday wear. It is also highly resistant to scratches and abrasions, which makes it a practical choice for rings, bracelets, and earrings. Blue Topaz is not sensitive to heat or light, so it can be cleaned and stored like most other gemstones.
Symbolism and Metaphysical Beliefs
Throughout history, gemstones have been attributed with symbolic meanings and metaphysical properties, and the December birthstones are no exception. These beliefs, rooted in ancient traditions and folklore, continue to influence the way people choose and wear their birthstones today.
Turquoise: The Stone of Protection
Turquoise has long been associated with protection, wisdom, and good fortune. In Ancient Egypt, it was believed to offer protection from evil spirits and misfortune, and it was often used in amulets and talismans to ward off danger. The Persians believed that turquoise could absorb the wearer's negative emotions and release them into the air, promoting calm and clarity.
In Native American cultures, turquoise is considered a bridge between the earth and sky, and it is often used in ceremonial regalia to connect the wearer to the spiritual world. Some traditions suggest that turquoise can change color or crack in response to danger, serving as a warning to the wearer. These beliefs have contributed to the stone's enduring popularity and cultural significance.
Tanzanite: The Stone of Clarity and Emotion
Tanzanite is often associated with clarity, intuition, and emotional balance. It is believed to help the wearer embrace their true self, release old emotional patterns, and embrace new perspectives. In modern metaphysical traditions, tanzanite is considered a stone of transformation, helping individuals navigate change and uncertainty with grace and confidence.
The trichroism of tanzanite is also seen as a symbol of transformation and diversity, reflecting the different aspects of the self and the ability to see things from multiple perspectives. This makes it a popular stone for meditation and self-reflection, as it is believed to enhance spiritual awareness and emotional healing.
Blue Zircon: The Stone of Prosperity and Healing
Blue Zircon is associated with prosperity, healing, and positive transformation. In ancient times, zircons were believed to ward off nightmares and bring good fortune, and blue zircons were particularly valued for their calming and purifying effects. It is also believed to enhance memory and mental clarity, making it a popular stone for students and professionals.
In modern metaphysical traditions, blue zircon is considered a stone of spiritual growth and emotional healing, helping individuals let go of past traumas and move forward with confidence. It is also believed to enhance intuition and psychic abilities, making it a valuable tool for meditation and spiritual exploration.
Blue Topaz: The Stone of Joy and Clarity
Blue Topaz is associated with joy, serenity, and mental clarity. It is believed to promote a sense of calm and peace, helping individuals navigate stressful situations with grace and composure. It is also associated with truth and honesty, encouraging the wearer to speak their mind and live in alignment with their values.
In modern metaphysical traditions, blue topaz is considered a stone of communication and emotional healing, helping individuals express their feelings and resolve conflicts with ease. It is also believed to enhance creativity and inspiration, making it a popular stone for artists and writers.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of December birthstones. Each gemstone has its own unique care requirements, based on its hardness, porosity, and sensitivity to light and temperature.
Turquoise: Delicate and Porous
Turquoise is one of the most delicate December birthstones, and it requires gentle care to avoid damage and discoloration. It should be kept away from water, oils, lotions, and cleaning agents, as these can penetrate the stone and alter its color. It should also be stored separately from harder gemstones to prevent scratches and abrasions.
To clean turquoise, a soft cloth and a small amount of water is usually sufficient. Avoid using ultrasonic or steam cleaners, as these can damage the stone's surface and structure. If the stone becomes dirty, a mild soap and water solution can be used, but it should be rinsed thoroughly and dried with a soft cloth.
Tanzanite: Sensitive to Heat and Light
Tanzanite is sensitive to heat, light, and sudden temperature changes, so it should be stored in a cool, dark place when not in use. It should also be kept away from direct sunlight for prolonged periods, as this can cause fading and discoloration.
To clean tanzanite, a soft cloth and a small amount of water is usually sufficient. If the stone becomes dirty, a mild soap and water solution can be used, but avoid using ultrasonic or steam cleaners, as these can damage the stone's structure.
Blue Zircon: Sparkling and Sensitive
Blue Zircon is a sparkling gemstone with a high refractive index, but it is also sensitive to heat. It should be stored in a cool, dark place and avoided from exposure to high temperatures, such as those used in ultrasonic or steam cleaners.
To clean blue zircon, a soft cloth and a small amount of water is usually sufficient. If the stone becomes dirty, a mild soap and water solution can be used, but it should be rinsed thoroughly and dried with a soft cloth.
Blue Topaz: Durable and Easy to Care For
Blue Topaz is one of the hardest December birthstones, and it is easy to care for. It is highly resistant to scratches and abrasions, making it suitable for everyday wear. It is also not sensitive to heat or light, so it can be cleaned and stored like most other gemstones.
To clean blue topaz, a soft cloth and a small amount of water is usually sufficient. If the stone becomes dirty, a mild soap and water solution can be used, and it can also be cleaned with ultrasonic or steam cleaners, as these will not damage the stone.
Conclusion
December’s birthstones—Turquoise, Tanzanite, Blue Zircon, and Blue Topaz—offer a diverse and beautiful collection of blue-hued gemstones, each with its own unique history, properties, and symbolism. From the ancient traditions surrounding Turquoise to the modern discovery of Tanzanite, these stones reflect the rich tapestry of human culture and the natural world.
Whether you are drawn to the soft, earthy tones of Turquoise, the dynamic colors of Tanzanite, the sparkling brilliance of Blue Zircon, or the calm and elegant beauty of Blue Topaz, December’s birthstones offer something for every taste and style. Their availability in a wide range of jewelry designs, from rings and pendants to earrings and bracelets, makes them a versatile and meaningful choice for those born in December.
As both symbolic and practical gemstones, these stones continue to be cherished and celebrated around the world. Whether worn for personal significance, spiritual meaning, or simply for their beauty, December’s birthstones are a testament to the enduring appeal of gemstones and their role in human history and culture.