December, the final month of the year, is symbolically rich and beautifully represented by three gemstones: turquoise, zircon, and tanzanite. Each of these stones carries its own distinct history, geological origin, and cultural significance, reflecting the diversity and depth of gemological tradition. While some months are associated with a single birthstone, December’s trio offers a broader spectrum of choice—allowing individuals to select a gemstone that aligns with their personal style, budget, or spiritual preferences. This article delves into the characteristics, history, and care of these three December birthstones, drawing on authoritative and well-documented sources to provide a comprehensive overview for gemstone enthusiasts and jewelry collectors alike.
Introduction
The concept of birthstones dates back to ancient times, with the earliest records found in the Breastplate of Aaron described in the biblical Book of Exodus. Over the centuries, various cultures have expanded and modified the list of birthstones, and in the modern era, the American National Association of Jewelers (now the Gemological Institute of America, or GIA) formalized the list in 1912. December, like a few other months, is unique in that it is associated with three gemstones, each with its own allure and meaning. These are:
- Turquoise, a soft, opaque gem with a long and storied history.
- Zircon, a dazzling gemstone that comes in a range of colors and is often heat-treated.
- Tanzanite, a relatively modern discovery known for its rich blue-violet hue and exclusivity.
Each of these stones not only serves as a personal emblem for those born in December but also offers a broader palette for jewelry design and spiritual connection. In the following sections, we will explore the geological formation, historical significance, and symbolic meanings of each gem, as well as practical advice for their care and appreciation.
History and Lore
Turquoise: The Stone of the Ancients
Turquoise is one of the oldest known gemstones, with archaeological evidence of its use dating back over 6,000 years. Ancient civilizations, including the Egyptians, Persians, and Chinese, prized turquoise for its beauty and believed it held protective and healing properties. In ancient Egypt, turquoise was used to adorn the mummies of pharaohs, signifying divine favor and immortality. The stone was also considered a symbol of the goddess Hathor, who was associated with love, music, and fertility.
The Chinese have a similarly long-standing tradition of using turquoise. Chinese artisans have been carving turquoise into intricate pendants and decorative objects for more than 3,000 years. In traditional Chinese culture, turquoise is believed to promote good health, prosperity, and spiritual balance.
During the 13th century, turquoise was believed to protect the wearer from falls—particularly from horses—and would break into pieces before a disaster occurred, acting as a warning. Hindu mystics of the same era believed that seeing turquoise after the new moon ensured wealth and fortune.
The name "turquoise" derives from the French phrase "pierre turquoise," meaning "Turkish stone." This name was given because the gem was first introduced to Europe through Turkey, even though it was not originally mined there. The term reflects the historical trade routes that brought turquoise from the East to the West.
Zircon: A Gemstone of Many Colors
Zircon is a less well-known but equally fascinating gemstone. Its name comes from the Arabic word "zarkun," meaning green, though zircon occurs in a wide range of colors, including blue, green, yellow, and red. Zircon has been used in jewelry for centuries, but it gained more popularity in the 20th century, especially after the development of heat treatment to enhance its colors.
Zircon is known for its high refractive index, which gives it a brilliant sparkle. Some sources suggest that zircon was mistaken for diamonds in ancient times due to its brilliance and fire. Zircon is also associated with spiritual awakening and is believed to enhance perception and clarity of thought.
In modern times, zircon is often used as a more affordable alternative to diamonds and other precious gemstones. It is particularly popular in vintage and Art Deco jewelry, where its bright colors and strong luster make it a standout choice.
Tanzanite: The Modern Discovery
Tanzanite is the youngest of the three December birthstones, having been discovered in 1967 in Tanzania. It was first identified by a local Maasai tribesman who stumbled upon a unique blue-violet crystal. The gem was later studied by a gemologist named Charles Leib and was eventually marketed as a new gemstone. The name "tanzanite" was chosen to reflect its country of origin, and it quickly gained popularity for its vibrant color and rarity.
Unlike turquoise and zircon, tanzanite is a relatively new player in the world of birthstones, and therefore its historical lore is not as extensive. However, it is associated with healing, protection, and self-transformation. Some modern sources suggest that tanzanite activates the throat, third-eye, and crown chakras, allowing the wearer to access psychic abilities and higher states of consciousness.
Due to its limited geographic source—Tanzania is the only place in the world where tanzanite is found—it is considered a rare and valuable gemstone. Its exclusivity, combined with its striking color, makes tanzanite a popular choice for those seeking a unique and meaningful December birthstone.
Geological Formation and Sources
Turquoise: From Copper Ores to Opaque Beauty
Turquoise is a phosphate mineral composed of copper, aluminum, and phosphorus. Its formation is closely tied to the weathering of copper ore deposits, particularly in arid regions. The process begins when rainwater or melted snow percolates through copper-rich rock. As the water moves through the ground, it reacts with copper sulfides, creating an acidic solution that carries dissolved copper.
This copper-rich water then interacts with aluminum and potassium in surrounding rocks, leading to the precipitation of turquoise in cavities and fractures. Turquoise is typically found in weathered volcanic rock and sedimentary rock in dry climates, where the low water content helps preserve the gemstone’s color and structure.
The most significant sources of turquoise are found in the southwestern United States, particularly in Arizona and Nevada, as well as in Mexico, China, and Tibet. These regions provide the ideal geological conditions for turquoise formation, with the presence of copper ores and the right chemical environment for precipitation.
Zircon: A Diverse and Hard-Wearing Gem
Zircon is a zirconium silicate mineral that occurs in a variety of colors, including blue, green, yellow, and red. Its colors are often enhanced through heat treatment, a process that has been used for centuries. Natural zircon can also exhibit high dispersion, giving it a diamond-like fire when cut and polished.
Zircon is found in igneous rocks, particularly in areas with granite and metamorphic rock formations. It is stable under high temperatures, making it suitable for industrial and decorative uses. Zircon is commonly mined in Sri Lanka, Australia, and Southeast Asia, where it is often found in association with sapphire sources.
Zircon’s Mohs hardness ranges from 6 to 7.5, making it relatively durable but still susceptible to abrasion. It is best suited for pendants, earrings, and brooches, where it is less likely to be subjected to harsh wear. Zircon is also known for its pleochroism, the ability to show different colors when viewed from different angles, a feature that adds to its visual appeal.
Tanzanite: A Unique Blue-Violet Crystal
Tanzanite is a trigonal mineral composed of calcium aluminum silicate. It is a trigonal variety of the mineral zoisite, and its color is due to the presence of vanadium. The gemstone was discovered in 1967 in Tanzania, and it has since become one of the most sought-after gemstones in the world.
Tanzanite is formed under specific geological conditions involving high pressure and temperature, which allow the vanadium to be incorporated into the crystal structure. The gem is only found in Tanzania, in the Merelani Hills near Arusha, making it one of the rarest gemstones in the world.
Due to its limited geographic source, tanzanite is considered a finite resource, and its value is expected to increase as the supply diminishes. The gem is heat-treated to enhance its color, which is typically blue to violet, but the treatment is permanent and does not affect the gem’s durability.
Tanzanite is rated at 6 to 7 on the Mohs scale, which means it is relatively soft and requires careful handling. It is also susceptible to heat and chemical exposure, making it unsuitable for everyday wear in settings such as rings or bracelets.
Gemological Properties
The gemological properties of a stone—such as hardness, refractive index, chemical composition, and optical characteristics—are crucial for understanding its use in jewelry and its durability over time. Below is a comparison of the key properties of the three December birthstones.
| Gemstone | Mohs Hardness | Color | Chemical Formula | Transparency | Optical Properties |
|---|---|---|---|---|---|
| Turquoise | 5–6 | Blue, green | CuAl₆(PO₄)₄(OH)₈·4H₂O | Opaque | Low refractive index, porous surface |
| Zircon | 6–7.5 | Multicolored | ZrSiO₄ | Translucent | High refractive index, strong dispersion |
| Tanzanite | 6–7 | Blue-violet | Ca₂Al₃(SiO₄)₃(OH) | Transparent | Strong pleochroism, high refractive index |
Turquoise: Soft and Porous
Turquoise is a relatively soft gemstone, with a Mohs hardness of 5 to 6, which means it can be easily scratched or broken. It is also porous and opaque, absorbing oils and dyes easily, which can alter its color over time. Turquoise is sensitive to water loss, and if it becomes dehydrated, it may change color or become brittle.
Zircon: Durable and Sparkling
Zircon is more durable than turquoise, with a hardness of 6 to 7.5. It is often heat-treated to enhance its color and stability. Zircon has a high refractive index, which gives it a bright luster and strong dispersion, similar to diamonds. It is stable under normal conditions but should be avoided in high-heat environments to prevent color fading.
Tanzanite: Rare and Delicate
Tanzanite is rated at 6 to 7 on the Mohs scale, making it relatively soft and prone to abrasion and cracking. It is heat-treated to stabilize its color, which is typically blue to violet. Tanzanite is susceptible to hydrochloric and hydrofluoric acids, and it can crack under sudden temperature changes. As such, it is best suited for pendants or earrings rather than rings or bracelets.
Symbolism and Metaphysical Beliefs
The three December birthstones each carry their own symbolic meanings and metaphysical properties, which have been passed down through history and are still practiced in modern gemstone traditions.
Turquoise: A Stone of Protection and Good Fortune
Turquoise has long been associated with protection, health, and good fortune. In ancient Egypt, it was believed to ward off evil and ensure safe travel. In Chinese tradition, turquoise is a symbol of harmony, longevity, and prosperity. It is also believed to balance the body’s energy and promote emotional stability.
Modern practitioners of metaphysical healing use turquoise to calm the mind, enhance communication, and promote spiritual growth. It is also associated with the throat and heart chakras, encouraging open and honest expression.
Zircon: A Gem of Clarity and Transformation
Zircon is believed to enhance perception, clarity, and spiritual awakening. It is often used in meditation and spiritual practices to help the wearer connect with higher states of consciousness. Zircon is also associated with love and compassion, promoting emotional balance and understanding.
Zircon is considered a stone of transformation, helping individuals let go of the past and embrace new possibilities. It is also believed to protect against negative energies and promote positive change in one’s life.
Tanzanite: A Stone of Healing and Intuition
Tanzanite is a modern gemstone but has quickly become associated with healing, intuition, and emotional balance. It is believed to activate the throat, third-eye, and crown chakras, allowing the wearer to access higher knowledge and spiritual insight.
Tanzanite is also associated with emotional healing, helping individuals process grief and move forward. It is believed to promote self-acceptance and inner peace, making it a valuable stone for personal growth and transformation.
Care and Cleaning
Proper care and cleaning are essential to maintaining the beauty and longevity of any gemstone. Below are specific recommendations for the care and cleaning of turquoise, zircon, and tanzanite.
Turquoise
- Hardness: 5–6 on the Mohs scale.
- Durability: Soft and porous.
- Cleaning: Use a soft cloth and mild soap in lukewarm water. Avoid ultrasonic and steam cleaners, which can damage the stone’s structure.
- Storage: Store in a cool, dry place, away from direct sunlight and moisture, to prevent color fading and dehydration.
Zircon
- Hardness: 6–7.5 on the Mohs scale.
- Durability: Relatively durable but can fade with prolonged exposure to light.
- Cleaning: Use a soft brush and mild soap in warm water. Avoid ultrasonic and steam cleaners, as they can alter the color of heat-treated zircon.
- Storage: Store in a soft pouch or separate compartment to prevent scratches and abrasions.
Tanzanite
- Hardness: 6–7 on the Mohs scale.
- Durability: Relatively soft and prone to cracking.
- Cleaning: Use warm, soapy water and a soft brush. Avoid ultrasonic and steam cleaners, which can damage the gemstone.
- Storage: Store in a soft cloth or padded box to prevent scratches and impacts. Avoid exposure to harsh chemicals and sudden temperature changes.
Conclusion
December’s birthstones—turquoise, zircon, and tanzanite—each offer a unique combination of beauty, history, and symbolism. Whether you prefer the soft and ancient turquoise, the sparkling and versatile zircon, or the rare and modern tanzanite, there is a December birthstone to suit every style and preference.
These gemstones are not only visually stunning but also rich in cultural and spiritual significance, making them a meaningful choice for jewelry and personal adornment. Understanding their geological origins, gemological properties, and care requirements allows you to appreciate and preserve their beauty for years to come.
For those born in December, selecting a birthstone is not just a matter of aesthetics—it is an opportunity to connect with history, tradition, and personal identity. Whether you choose one or all three, these December gemstones are a testament to the enduring allure of the natural world and the human fascination with the beauty of minerals.