The month of December is uniquely represented by a trio of distinct blue gemstones: Tanzanite, Zircon, and Turquoise. While all three share a color palette reminiscent of winter skies and icy waters, Turquoise stands apart as perhaps the most historically significant and culturally pervasive of the group. For individuals born on December 20th, Turquoise is specifically identified as their birthstone, a designation rooted in centuries of tradition. This gemstone, characterized by its opaque blue-green hues, has traversed the globe, been revered by empires and indigenous tribes alike, and continues to hold a prominent place in modern jewelry. Its appeal lies not only in its distinctive color but in a rich tapestry of lore that attributes protective and balancing properties to the stone. To understand the significance of Turquoise is to explore its geological origins, its journey through human history, and the specific gemological properties that define it.
History and Lore: A Global Talisman
The history of Turquoise is as ancient and complex as the veins of copper that color it. The gemstone derives its name from the French phrase pierre turquoise, meaning "Turkish stone." This nomenclature offers a clue to its introduction to Europe; the stone was initially brought to the West through trade routes originating in Turkey. However, the stone’s origins and use predate its European naming by millennia.
Turquoise has been mined and utilized by civilizations across the world for thousands of years. Ancient Egyptians prized the gemstone, incorporating it into the adornments of pharaohs and using it to decorate burial masks. The protection it offered was believed to extend into the afterlife. Similarly, in the Persian Empire, Turquoise was a ubiquitous protective talisman. It was widely believed to ward off unnatural death and injury, acting as a shield against negative energies. The stone was so integral to Persian culture that it was often set into jewelry and weaponry, serving as a constant guardian for the wearer.
In the Americas, Turquoise holds profound spiritual significance among Native American tribes, particularly in the Southwest. Here, the stone is not merely an ornament but a piece of the sky that has fallen to earth. It symbolizes purity, serenity, and the unity of the elements. The color of the stone is directly associated with the sky and the ocean, reinforcing its connection to the vastness of nature. The GIA (Gemological Institute of America) notes that Turquoise has adorned everything from ancient Egyptian pharaohs' burial masks to the intricate jewelry of the Navajo, Zuni, and Hopi peoples.
The journey of Turquoise to becoming a modern birthstone is a more recent development. The concept of birthstones is largely derived from the Breastplate of Aaron, a religious garment described in the Book of Exodus, which featured twelve stones representing the twelve tribes of Israel. Over centuries, these stones were associated with the twelve signs of the zodiac and eventually the months of the year. While the modern list of birthstones was standardized in 1912 by the National Association of Jewelers, Turquoise has consistently been recognized for December. Sources confirm that December-born individuals are blessed with a "blue trio" of gemstones, but Turquoise remains the traditional anchor, particularly for specific dates like December 20th.
Geological Formation and Sources
Turquoise is an opaque, blue-to-green mineral that belongs to the phosphate class. It is a hydrous phosphate of aluminum that contains copper, which is responsible for its characteristic blue color, and sometimes iron, which creates greenish hues. Unlike many gemstones that crystallize in igneous or metamorphic environments, Turquoise forms in arid regions as a secondary mineral in the presence of water. It occurs when water containing dissolved copper and aluminum percolates through rocks rich in phosphorus. As the water evaporates or reacts with the host rock, Turquoise deposits form in nodules, veins, or as crusts on the host rock.
The geographical distribution of Turquoise is restricted to specific regions of the world where these geological conditions exist. Historically, the finest quality Turquoise came from Persia (modern-day Iran), known for its uniform, sky-blue color without matrix (the host rock veins running through the stone). In the United States, the Southwest is the primary source, particularly in Arizona, New Mexico, and Nevada. The stones from these regions often exhibit a distinct matrix, which can range from a spiderweb pattern to a more chaotic interlocking of the host rock.
The sources provided do not detail specific modern mining locations for Turquoise in the same way they do for Tanzanite (found only near Mount Kilimanjaro). However, the historical references to Persian and Native American sources highlight the gem's long-standing association with specific geological belts. The formation process is slow and the deposits are often small and difficult to mine, contributing to the value of the stone. Because Turquoise is relatively soft and porous in its natural state, it is rarely found in large, flawless crystals.
Gemological Properties
Understanding the physical and chemical properties of Turquoise is essential for both jewelers and collectors. As an opaque gemstone, its value is determined primarily by color, hardness, and the presence or absence of matrix.
Color: The most prized color of Turquoise is an even, medium to medium-light blue, often referred to as "sky blue" or "robin's egg blue." Greenish tones are common and generally less valuable, though some collectors prefer the unique hues of "apple green" Turquoise. The color is directly linked to the presence of copper (blue) and iron (green).
Hardness and Durability: On the Mohs scale of mineral hardness, Turquoise ranks between 5 and 6. This makes it a relatively soft gemstone compared to Sapphire (9) or Diamond (10). Consequently, it is susceptible to scratching and abrasion. It also possesses a specific gravity of 2.60 to 2.90 and is cryptocrystalline, meaning it is composed of microscopic crystals that are not easily distinguishable.
Chemical Composition: The general chemical formula for Turquoise is $CuAl6(PO4)4(OH)8 \cdot 4H_2O$. The water content is crucial; heating Turquoise can cause it to dehydrate, leading to discoloration or crazing (a network of fine cracks).
Treatments: Because natural Turquoise is often porous and varies widely in hardness, it is frequently treated to enhance durability and color. Stabilization involves impregnating the stone with a clear resin or wax to harden it and prevent it from absorbing oils and dirt. Dyeing is also common to improve color uniformity. However, sources emphasize that high-quality, natural, untreated Turquoise remains the most valuable.
The following table summarizes the key gemological properties of Turquoise based on standard gemological references:
| Property | Description |
|---|---|
| Mineral Species | Turquoise |
| Chemical Formula | $CuAl6(PO4)4(OH)8 \cdot 4H_2O$ |
| Color | Blue to green; shades depend on copper and iron content |
| Hardness (Mohs) | 5 – 6 |
| Crystal System | Triclinic (cryptocrystalline) |
| Transparency | Opaque |
| Refractive Index | 1.610 – 1.650 |
| Specific Gravity | 2.60 – 2.90 |
Symbolism and Metaphysical Beliefs
The allure of Turquoise extends far beyond its physical beauty; it is deeply rooted in symbolism and metaphysical beliefs that span cultures and eras. The stone is almost universally associated with protection, healing, and communication.
Protective Talisman: As noted in historical accounts, Turquoise has long been viewed as a shield. In many cultures, it was worn to deflect evil eye, ward off negative spirits, and prevent accidents. This belief was so strong that Turquoise was often set into the hilts of swords and daggers to ensure victory and safety in battle.
Balance and Harmony: The serene blue-green hues are psychologically linked to calmness and balance. Metaphysical traditions suggest that Turquoise helps align the chakras and harmonize the energies of the body, mind, and spirit. It is often described as a grounding stone that brings peace of mind and emotional stability.
Communication and Self-Expression: For those born on December 20th, the stone is said to influence personal growth by enhancing communication. It is thought to encourage honest and open expression, helping the wearer articulate thoughts and emotions with clarity. This aligns with the stone's association with the throat chakra, which governs speech and truth.
Birthstone Specifics: For the December 20th individual, sources suggest that Turquoise embodies specific personal attributes. Those born on this date are believed to possess a deep sense of empathy and strong intuition. The stone is thought to amplify these natural traits, helping them navigate complex social dynamics and maintain harmonious relationships.
Care and Cleaning
Due to its relatively low hardness and porous nature, Turquoise requires careful handling and specific cleaning methods to maintain its luster and integrity. It is not a gemstone that can be treated with the same roughness as harder stones like Sapphire or Ruby.
Storage: Turquoise should be stored separately from other jewelry to prevent scratching. It is advisable to keep it in a soft cloth pouch or a lined jewelry box.
Cleaning: The recommended method for cleaning Turquoise is warm, soapy water with a soft brush. It is crucial to avoid harsh chemicals, as they can damage the stone or strip away any stabilizing treatments or wax finishes. One should never use bleach, ammonia, or abrasive cleaners.
Exposure: Turquoise is sensitive to heat and sudden temperature changes. Prolonged exposure to direct sunlight can cause the color to fade, and extreme heat can cause the stone to crack or dehydrate. Additionally, cosmetics, hairsprays, and perfumes can tarnish the stone over time. It is best to put on Turquoise jewelry after applying makeup and perfumes and to wipe it clean after wear.
Durability Limitations: Because of its hardness, Turquoise is not recommended for rings worn daily, particularly for those with an active lifestyle. It is better suited for pendants, earrings, and occasional-wear rings where it is less likely to suffer impacts. If set in a ring, a protective mounting (such as a bezel setting) is preferable to a prong setting.
Conclusion
Turquoise remains one of the most recognizable and culturally significant gemstones in the world. As the birthstone for December, and specifically for those born on December 20th, it offers a connection to a lineage of history that includes ancient Egyptians, Persian warriors, and Native American tribes. Its value is defined not just by its chemical composition or hardness, but by the rich blue-green color that has inspired legends of protection, balance, and clear communication. While it requires more care than many modern gemstones, the enduring popularity of Turquoise speaks to its timeless appeal. Whether valued for its metaphysical properties, its geological rarity, or its aesthetic beauty, Turquoise continues to be a gemstone of profound depth and enduring elegance.