The month of December is uniquely associated with three distinct gemstones: turquoise, tanzanite, and zircon. Each offers a unique interpretation of the color blue, providing a diverse palette for those born in the year's final month. This article delves into the geological origins, gemological properties, historical significance, and cultural symbolism of these three birthstones, drawing exclusively from the provided source materials. While turquoise is an ancient opaque mineral, tanzanite is a modern discovery prized for its violet-blue hue, and zircon is a traditional gem known for its brilliant fire. Together, they represent a fascinating spectrum of December's birthstones.
History and Lore
The history of December's birthstones spans from ancient civilizations to modern geological discoveries. Turquoise holds the most ancient claim, with evidence of its use by Native Americans in the southwestern United States over 2,000 years ago. There, ancient artists crafted beads, pendants, inlay work, and small sculptures from this stone, and it remains an integral part of Southwestern culture today.
In contrast, tanzanite is a product of the 20th century. It was added to most birthstone lists in 1952, a time when topaz (another November birthstone) was relatively costly. The discovery of large deposits in Brazil later helped reduce the price of topaz, but tanzanite's inclusion as a December stone marked a significant modernization of birthstone lists. This addition reflects a broader trend in the 20th century where jewelers, seeking to streamline birthstone charts, introduced new and accessible gems. The modern birthstone chart became standardized in 1912, and since then, jewelers have continued to add options. For December, spinel, citrine, and tanzanite are cited as recent modern additions to the traditional lists.
Zircon, another December birthstone, has a long history as a gemstone. It is a bright gem with high luster, and many specimens produce a colorful fire that is similar to diamond. Its historical use is not detailed in the provided sources, but its inclusion in traditional birthstone charts, such as the one that lists turquoise and lapis lazuli for December, indicates its long-standing place in gemology.
The journey of these stones to becoming modern birthstones is part of a larger narrative. The ancient birthstone chart, also known as the "Mystical" chart, was slightly more exotic in its gemstone selection, but the chosen stones didn't precisely align with the Gregorian calendar, making it confusing for modern people. The modern chart, established by jewelers in 1912, aimed for a streamlined system. Today, people in the United States draw freely from both traditional and modern lists, choosing stones that appeal to them. Some traditional gems, like turquoise, remain popular due to being less expensive or more readily available than their modern counterparts.
Geological Formation and Sources
The three December birthstones originate from vastly different geological processes and are sourced from specific global locations.
Turquoise is a blue to blue-green to yellowish green mineral. It is formed in arid regions where acidic, copper-rich groundwater percolates through rocks containing aluminum and phosphorus. The sources indicate that turquoise is mined around the world. In the United States, its historical and cultural significance is deeply tied to the Southwest, where it has been used for millennia. As an opaque gemstone, it is typically cut into cabochon shapes, often freeform, to maximize the use of the rough material rather than being cut into calibrated shapes and sizes.
Tanzanite is a more recent discovery. The provided sources do not specify its exact mining locations, but they note that it is mined around the world. Its formation is linked to specific geological conditions, but the details are not elaborated upon in the provided chunks. As a birthstone added in 1952, its sources are likely concentrated in regions that began commercial production in the mid-20th century.
Zircon is a bright gem with high luster. The sources do not detail its specific formation process or primary mining locations, only stating that it is mined around the world. It is known for producing a colorful fire similar to diamond, which is a key characteristic of its gemological appeal.
The sources collectively emphasize that all three December birthstones are mined around the world, contributing to their global availability and varied market prices.
Gemological Properties
The gemological properties of turquoise, tanzanite, and zircon are distinct, influencing their use in jewelry, durability, and care requirements. The following table summarizes key properties based on the provided data:
| Gemstone | Color Range | Hardness (Mohs Scale) | Key Properties & Notes |
|---|---|---|---|
| Turquoise | Blue, blue-green, yellowish green | 5-6 (Low hardness) | Opaque; easily scratched; often set in sterling silver; cut into cabochons. |
| Tanzanite | Blue, purple | 6.5-7 | Prone to breakage; has perfect cleavage and will break easily. |
| Zircon | Various (bright gem) | 6.5-7 | Prone to breakage; high luster; produces colorful fire similar to diamond. |
Color and Clarity: - Turquoise is prized for its blue to green hues, with bright blue being the most preferred color. Its opacity is a defining characteristic. - Tanzanite is known for its unique take on the color blue, specifically a violet-blue hue. The sources list its color as "Blue/Purple" in the birthstone chart. - Zircon is described as a bright gem with high luster and colorful fire, though its specific color range is not detailed in the provided chunks.
Hardness and Durability: Hardness is a critical factor in gemstone durability and care. The Mohs scale ranges from 1 (softest) to 10 (hardest). - Turquoise has a low hardness, typically between 5 and 6 on the Mohs scale. This makes it easily scratched and requires careful handling. Its low hardness is a key reason it is often set in protective settings like bezels and is popular in casual, everyday jewelry. - Tanzanite and Zircon both have a hardness of 6.5-7 on the Mohs scale. However, hardness is not the only factor in durability. Both stones are noted to be prone to breakage. Tanzanite is specifically described as having "perfect cleavage and will break easily." Zircon, while having a similar hardness, is also listed as prone to breakage. This means both stones require careful handling to avoid impacts that could cause chipping or cleavage.
Cut and Setting: - Turquoise is almost exclusively cut into cabochons (smooth, rounded domes) due to its opacity. The sources note it is often set into sterling silver jewelry, a traditional and popular pairing. - Tanzanite and Zircon, being transparent to translucent gems, can be cut into faceted shapes to maximize their brilliance and fire. However, their susceptibility to breakage necessitates secure settings in jewelry.
Symbolism and Metaphysical Beliefs
The symbolism and metaphysical beliefs associated with the December birthstones are drawn from cultural traditions and modern interpretations.
Turquoise carries deep cultural significance, particularly in the American Southwest, where it has been used for over 2,000 years. It is described as an important part of Southwestern culture, symbolizing a connection to heritage and tradition. While specific metaphysical properties are not detailed in the provided sources for turquoise, its long-standing use in art and jewelry suggests a profound symbolic value beyond mere adornment.
Tanzanite is associated with modern metaphysical beliefs. The provided birthstone chart lists its key symbolism as "Protection, Healing, Wisdom." This aligns with a general trend of attributing healing and protective properties to gemstones, though the sources do not elaborate on the historical or cultural origins of these specific beliefs for tanzanite.
Zircon is similarly listed with the symbolism "Protection, Healing, Wisdom" in the same chart. This shared symbolism with tanzanite may reflect contemporary gemstone lore rather than ancient traditions. The sources do not provide historical context for zircon's symbolic meanings, focusing instead on its physical properties like luster and fire.
It is important to note that the provided sources offer limited information on the historical lore and metaphysical beliefs for these stones, particularly for tanzanite and zircon. The symbolic meanings presented here are based on the modern birthstone chart data within the sources. For turquoise, the historical and cultural significance is more clearly documented, though its specific symbolic attributes in the context of birthstone lore are not elaborated upon.
Care and Cleaning
Proper care is essential for maintaining the beauty and integrity of these gemstones, given their varying physical properties.
Turquoise requires the most careful handling due to its low hardness (5-6). It is easily scratched by harder materials and even dust. To clean turquoise, use only warm water, a soft cloth, and mild soap. Avoid ultrasonic cleaners, steam cleaners, and harsh chemicals, which can damage the stone or its porous surface. It is also advisable to store turquoise jewelry separately to prevent scratches from other gems. Because of its porosity, it can absorb oils and cosmetics, so it should be put on after applying lotions and perfumes.
Tanzanite and Zircon, both with a hardness of 6.5-7, are more resistant to scratching than turquoise but are prone to breakage due to perfect cleavage (tanzanite) or general fragility (zircon). This means they can be damaged by sharp blows or pressure. Cleaning should be done with warm soapy water and a soft brush. Avoid ultrasonic cleaners, as the vibrations can cause internal fractures or exacerbate existing cleavage planes. Sudden temperature changes should also be avoided. Given their cleavage, it is crucial to handle them with care and store them in padded compartments to prevent impact.
For all three gemstones, regular gentle cleaning is sufficient. When in doubt, consulting a professional jeweler is recommended, especially for pieces with intricate settings or for stones that have been worn for many years.
Conclusion
The December birthstones—turquoise, tanzanite, and zircon—offer a remarkable diversity within the realm of gemology. Turquoise stands as an ancient, opaque mineral with deep cultural roots in the American Southwest, valued for its soothing blue-green hues and historical significance. Tanzanite represents modern gemology, a 20th-century discovery that introduced a vibrant violet-blue option to the birthstone list, prized for its unique color but requiring careful handling due to its perfect cleavage. Zircon, a traditional gem with brilliant fire and luster, completes the trio, offering a bright, diamond-like alternative with its own set of durability considerations.
Their shared month belies their distinct origins, properties, and symbolism. From the ancient artisan beads of turquoise to the recently added tanzanite and the historically cherished zircon, these stones provide a wide spectrum of choices for those seeking a personal gemstone. Understanding their geological backgrounds, gemological characteristics—particularly their hardness and cleavage—and historical contexts allows enthusiasts, buyers, and students to appreciate not just their beauty, but their unique place in the world of birthstones. As the sources indicate, modern consumers freely choose from these options, selecting the stone that best fits their style and resonates with their personal connection to the month of December.