December 17 falls within the month of December, a month symbolically rich in celebration and transition. It is also a date associated with the birthstone tradition — a practice that has evolved over centuries, combining mineralogy, culture, and spirituality. For those born on December 17, the birthstone choices include turquoise, zircon (particularly blue zircon), and tanzanite. These three gemstones, while distinct in their physical and metaphysical properties, share a common thread: they are all associated with December and offer unique meanings, histories, and applications in jewelry and spiritual practices.
This article explores the gemstones linked to December 17, delving into their geological formation, historical significance, and cultural symbolism. Drawing from authoritative and historical sources, it provides a comprehensive overview for gemstone enthusiasts, jewelry buyers, and students of gemology.
Introduction
December is one of the few months in the birthstone tradition that has more than one designated gemstone. This multiplicity is not arbitrary but rather a reflection of historical evolution, geological availability, and cultural preferences. For December 17, the primary birthstone options are turquoise, zircon, and tanzanite. Each of these stones has a unique history, scientific composition, and spiritual significance.
The inclusion of multiple gemstones in the December birthstone list is partly due to the desire to provide more affordable and accessible options alongside the traditional and rarer stones. For instance, while turquoise is ancient and has been used for thousands of years, tanzanite is a modern discovery from the 1960s. Zircon, particularly the blue variety, serves as a bridge between these eras, offering a blend of antiquity and contemporary appeal.
This article will explore the three December 17 birthstones in detail, covering their geological properties, historical usage, and cultural symbolism. It will also touch on their care and value, providing readers with a well-rounded understanding of these fascinating gemstones.
History and Lore
The Evolution of December Birthstones
The modern concept of birthstones has roots in ancient texts, particularly the Breastplate of Aaron described in the Bible. According to this text, each of the twelve tribes of Israel was represented by a gemstone. Over time, these stones were assigned to the months of the year, and the tradition gradually evolved into the contemporary birthstone list we recognize today.
In the case of December, the earliest known birthstone was ruby. This association, however, has largely faded from modern usage. By the 19th century, turquoise was being promoted as a December birthstone, particularly by jewelers such as Tiffany & Co., who included it in their birthstone poems. In the early 20th century, the National Association of Jewellers (now Jewellers of America) added lapis lazuli as an alternative. However, by the 1950s, lapis lazuli was replaced by zircon, and in 2002, tanzanite was officially added as a December birthstone.
The inclusion of multiple gemstones for December reflects both practical and cultural considerations. As gemstone sources and technologies have changed, so too has the birthstone list, ensuring that there are options available for different tastes, budgets, and traditions.
Cultural Significance and Symbolism
Across various cultures, the December gemstones have been imbued with deep meaning and spiritual significance.
Turquoise has long been regarded as a protective and healing stone. Ancient civilizations, including the Egyptians, Chinese, and Native Americans, used turquoise in amulets and jewelry to ward off evil, promote health, and bring good fortune. In medieval times, it was believed to be a stone of divination and truth. Today, it is still valued for its calming properties and is considered especially beneficial for those born under the zodiac sign of Sagittarius.
Zircon, particularly in its blue variety, has been used since ancient times as a gemstone and even as a diamond substitute. Known for its brilliance and refractive index, blue zircon is often associated with joy and emotional balance. In some cultures, it is believed to enhance wisdom and provide clarity of thought.
Tanzanite, the newest of the December birthstones, is unique in that it is found only in Tanzania. Discovered in the 1960s, it was marketed as a December birthstone in the early 2000s. It is admired for its vibrant blue-violet hues and is believed to be a stone of transformation, intuition, and spiritual awakening.
These stones, while different in their histories, share a common thread: they are all connected to the idea of protection, transformation, and spiritual insight. For someone born on December 17, any of these gemstones can serve as a meaningful and powerful symbol.
Geological Formation and Sources
Understanding the geological origins of the December 17 birthstones provides insight into their rarity, availability, and characteristics.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper. It forms in arid regions where copper deposits are exposed to the surface, allowing for the interaction of water with copper sulfides. This process leads to the precipitation of turquoise in cavities and weathered rock. Turquoise is typically found in weathered volcanic rock and sedimentary rock, and its formation is closely tied to the presence of copper ore.
The most notable sources of turquoise include the United States (especially Nevada and New Mexico), Iran, and Egypt. These locations have produced some of the finest turquoise in history. The stone is relatively soft, with a Mohs hardness of 5 to 6, making it prone to scratches and damage from oils and moisture.
Zircon
Zircon is a silicate mineral that can occur in a wide range of colors, including blue, yellow, red, and brown. The blue variety, which is most commonly associated with December, is often heat-treated to enhance its color. Zircon is known for its high refractive index and brilliance, which make it a popular alternative to diamonds and other precious gemstones.
Zircon is found in several countries, including Thailand, Cambodia, and Vietnam. Some zircon specimens have been used in the development of radiometric dating due to their trace amounts of uranium and thorium. The oldest known zircon crystals are over 4.4 billion years old, making them among the oldest minerals found on Earth.
Tanzanite
Tanzanite is a variety of the mineral zoisite and is unique to Tanzania, near Mount Kilimanjaro. It is a relatively new gemstone, discovered in the 1960s and first marketed by Tiffany & Co. What makes tanzanite particularly interesting is its strong pleochroism — the ability to display different colors when viewed from different angles. Tanzanite can appear blue, purple, or even brown, depending on the lighting and viewing angle.
The rarity of tanzanite contributes to its value and desirability. It is typically heat-treated to enhance its color and is cut into a variety of shapes to showcase its brilliance. Due to its limited geographic source, tanzanite is considered a gemstone of the future, with increasing demand and limited supply.
Gemological Properties
A detailed understanding of the gemological properties of each December 17 birthstone is essential for both collectors and jewelers.
Turquoise
| Property | Value |
|---|---|
| Chemical Formula | CuAl₆(PO₄)₄(OH)₈·4H₂O |
| Color | Blue, green, and white |
| Hardness (Mohs) | 5–6 |
| Specific Gravity | 2.6–2.8 |
| Luster | Waxy, vitreous |
| Transparency | Opaque |
| Inclusions | Common |
Turquoise is typically opaque and porous, which makes it susceptible to damage from oils and moisture. It is often stabilized with resins to enhance durability and color retention. In jewelry, it is frequently used in inlay and cabochon form.
Zircon
| Property | Value |
|---|---|
| Chemical Formula | ZrSiO₄ |
| Color | Blue, yellow, red, brown |
| Hardness (Mohs) | 6–7.5 |
| Specific Gravity | 4.6–4.8 |
| Luster | Vitreous |
| Transparency | Transparent to translucent |
| Inclusions | Common |
Blue zircon is the most popular variety for December birthstones. It is known for its high refractive index and brilliance. Zircon can be heat-treated to enhance its color, and it is sometimes confused with other gemstones like topaz or sapphire. Its durability is good, but it can be brittle in certain directions.
Tanzanite
| Property | Value |
|---|---|
| Chemical Formula | Ca₂Al₃(SiO₄)₃(OH) |
| Color | Blue, purple |
| Hardness (Mohs) | 6–7 |
| Specific Gravity | 3.3–3.4 |
| Luster | Vitreous |
| Transparency | Transparent |
| Inclusions | Common |
Tanzanite is prized for its vibrant color and strong pleochroism. It is typically heat-treated to enhance its blue-violet hues. The stone is relatively durable but should be handled with care to avoid scratches and fractures. Tanzanite is often cut in step or mixed cuts to maximize its brilliance and color display.
Symbolism and Metaphysical Beliefs
The December 17 birthstones are not only valued for their beauty and rarity but also for their symbolic and spiritual significance. These beliefs have been passed down through generations and are still practiced in various forms today.
Turquoise
In ancient times, turquoise was considered a stone of protection and healing. It was used in amulets and talismans to ward off evil and bring good fortune. In Native American traditions, turquoise is associated with the sky and water and is believed to promote vitality and spiritual connection.
In modern metaphysical practices, turquoise is thought to enhance communication, calm the mind, and encourage emotional balance. It is also associated with the throat and heart chakras, making it a popular stone for meditation and healing.
Zircon
Zircon, particularly in its blue form, is associated with joy, emotional balance, and clarity of thought. It is believed to enhance wisdom and provide insight into one’s spiritual path. In some traditions, zircon is considered a stone of transformation and renewal, helping individuals navigate change and uncertainty.
Blue zircon is also linked to the heart and throat chakras, promoting open and honest communication. It is considered a protective stone, helping to shield the wearer from negative energies.
Tanzanite
Tanzanite is a relatively new addition to the birthstone list but has quickly gained popularity in metaphysical circles. It is associated with spiritual awakening, intuition, and emotional healing. Tanzanite is believed to help individuals access higher states of consciousness and connect with their inner wisdom.
The stone is also thought to aid in the release of old patterns and behaviors, making it a powerful tool for personal transformation. It is often used in meditation and energy work, particularly for those seeking to deepen their spiritual practice.
Care and Cleaning
Proper care is essential for preserving the beauty and value of the December 17 birthstones. Each stone has specific requirements based on its hardness, porosity, and sensitivity to light and heat.
Turquoise
Turquoise is a relatively soft and porous gemstone, so it requires gentle handling. It should be stored in a dry, cool place to prevent moisture from causing discoloration. Avoid exposing it to direct sunlight, as this can cause the color to fade. Cleaning should be done with a soft cloth and mild soap. Ultrasonic and steam cleaners should be avoided, as they can damage the stone.
Zircon
Zircon is more durable than turquoise but still requires careful cleaning. It can be cleaned with warm water and mild soap. Ultrasonic cleaners are generally safe for zircon, but steam cleaners should be used with caution. Zircon should be stored separately from harder gemstones to prevent scratches.
Tanzanite
Tanzanite is a relatively tough gemstone but should still be handled with care. It can be cleaned with warm water and mild soap. Ultrasonic and steam cleaners are generally safe, but it is best to avoid exposing tanzanite to extreme temperatures. It should be stored in a dry place to prevent the development of surface haze.
Conclusion
The December 17 birthstones — turquoise, zircon, and tanzanite — are more than just beautiful gemstones; they are symbols of protection, transformation, and spiritual insight. Each stone has a rich history, unique geological properties, and deep cultural significance. Whether you are a collector, a jewelry buyer, or a student of gemology, these stones offer a fascinating glimpse into the world of birthstones and their enduring appeal.
For those born on December 17, these gemstones provide not only a meaningful connection to their birth month but also a powerful tool for personal growth and healing. Whether you choose turquoise for its ancient wisdom, zircon for its clarity and brilliance, or tanzanite for its vibrant energy, each stone offers its own unique benefits and beauty.