December is a unique month in the world of birthstones, distinguished by its association with not one, but four distinct gemstones: Blue Topaz, Turquoise, Tanzanite, and Zircon. This multiplicity is unparalleled among the months, offering those born in the final month of the year a diverse palette of blue hues, from the icy clarity of sky blue to the deep, shifting tones of violet-blue. The tradition reflects a blend of ancient lore and modern gemological discovery, providing options that range from one of the oldest known gems to a mineral first identified in the 20th century. The selection includes stones that are exceptionally durable for daily wear and others that require more careful handling, yet all share a common thematic connection to the cool, serene colors of the winter season. This article will explore the history, geological origins, gemological properties, and cultural significance of each of December’s four birthstones, drawing exclusively from the provided source materials to provide an authoritative and comprehensive guide for gemstone enthusiasts, jewelry buyers, and students of gemology.
History and Lore: A Tapestry of Time and Tradition
The journey to December’s current birthstone list is a story of evolving customs and commercial practicality. The tradition of associating gemstones with specific months has roots in ancient cultures, but the standardized list used today in the United States was largely formalized in the 20th century. In 1912, the National Association of Jewelers created an official list, which combined historical customs with gemstones that were practical for jewelry companies to sell. This list was updated in 1952 by the Jewelry Industry Council of America, which added zircon to December’s offerings. The most recent addition was tanzanite, which was included in 2002, reflecting the gem’s rising popularity and commercial significance.
The reason December was granted four birthstones is not definitively known, though sources suggest it was to provide more affordable options and greater variety in color and style. As new gemstones were discovered and commercial markets expanded, the birthstone list evolved to meet consumer demand. This is evident in the additions of zircon and tanzanite, which offered new and exciting choices for December-born individuals.
Among the four, turquoise stands out for its profound antiquity. It is one of the oldest known gemstones, with a history spanning thousands of years. It has been used extensively in jewelry, amulets, and decorative objects across numerous ancient cultures, signifying its enduring appeal and cultural importance long before it was formally designated as a birthstone.
In contrast, blue topaz has a more ambiguous historical origin. The exact historical origin of blue topaz is unknown, as it has been found throughout history, though its specific early uses are not detailed in the available sources. The word "topaz" itself is believed to derive from the Sanskrit word "tapas," meaning fire, and historically, topaz was associated with strength and protection. Its modern designation as a birthstone for December solidified its place in contemporary jewelry.
Tanzanite’s history is notably brief, being a relatively new discovery in the gem world. Its addition to the birthstone list in 2002 marks it as a modern gemstone, celebrated for its unique color and rarity.
Zircon, while ancient, has a complex history often clouded by confusion with other gemstones, particularly cubic zirconia, a synthetic material. However, natural blue zircon has been valued for its brilliance and fire, contributing to its inclusion as a December birthstone in the mid-20th century.
Geological Formation and Sources
Each of December’s birthstones forms under different geological conditions and is mined in specific regions of the world, contributing to their rarity and value.
Blue Topaz is mined in several countries, including Sri Lanka, Brazil, Mexico, Nigeria, and the United States. In the U.S., it is particularly noted for its occurrence in states like Texas, where it holds the honor of being the official state gem, as well as Utah and California. It is important to note that naturally occurring blue topaz is rare; most of the blue topaz available on the market is the result of heat-treating colorless topaz to achieve its desired blue color.
Turquoise is an opaque mineral that forms in arid regions where acidic water percolates through rocks containing aluminum and copper. While specific mining locations are not listed in the provided sources, its formation is tied to these specific geological processes. The sources emphasize that turquoise is a relatively soft and porous gemstone, which affects its durability and care.
Tanzanite is celebrated for its extreme rarity, as it is mined in only one specific region of the world: a small area in Tanzania, East Africa. This singular source makes tanzanite one of the rarest gemstones known. Due to its limited geographic origin and high demand, it is also the most expensive of the four December birthstones.
Zircon is a mineral that forms in a variety of geological environments, often in igneous and metamorphic rocks. While the sources do not specify particular mining countries for blue zircon, its presence on the birthstone list indicates its availability in the gem market, often from sources in countries like Cambodia, Sri Lanka, and Australia.
Gemological Properties
Understanding the physical and chemical properties of these gemstones is crucial for their use in jewelry, their care, and their valuation. The table below summarizes the key gemological data for Blue Topaz and Turquoise, as detailed in the provided sources.
| Property | Blue Topaz | Turquoise |
|---|---|---|
| Hardness (Mohs scale) | 8 | 5–6 |
| Color | Blue (natural or heat-treated) | Blue to green |
| Refractive Index | 1.62–1.64 | 1.61–1.65 |
| Specific Gravity | 3.5–3.6 | 2.6–2.8 |
| Transparency | Transparent to translucent | Opaque |
| Cleavage | None | None |
| Durability | High; suitable for everyday wear | Low to moderate |
Blue Topaz is the most durable of the December birthstones for everyday wear. With a hardness of 8 on the Mohs scale, it is resistant to scratches and can withstand daily use. Its transparency ranges from transparent to translucent, and it lacks cleavage, which means it is less likely to split along planes. However, it can be damaged by exposure to high heat or harsh chemicals, so appropriate care is necessary during cleaning.
Turquoise, with a hardness of only 5–6, is considerably softer. Its porous nature makes it susceptible to scratching, chipping, and absorption of oils, dyes, and moisture. Changes in moisture and temperature can also affect its stability. While it has no cleavage, its low durability means it is better suited for jewelry that is not subjected to rough wear, such as pendants or earrings, rather than rings.
The gemological properties for Tanzanite and Zircon are not fully detailed in the provided sources. However, it is noted that tanzanite is also considered fragile, which aligns with its lower hardness and the need for careful handling. Zircon, while not described in detail, is known for its high brilliance and fire, and it is generally more durable than tanzanite and turquoise, though less so than blue topaz.
Symbolism and Metaphysical Beliefs
Across cultures and history, gemstones have been imbued with symbolic meanings and metaphysical properties, and December’s birthstones are no exception. These beliefs add a layer of personal significance to the stones beyond their physical beauty.
Blue Topaz is modernly associated with calmness, love, and clarity. Its serene blue color is said to evoke a sense of peace, making it a symbol of tranquil emotions and clear communication. In historical contexts, topaz was linked to strength and protection, a tradition that carries forward in its symbolic weight.
Turquoise is strongly tied to themes of protection and good fortune. As one of the oldest known gems, it has been used for millennia as an amulet to ward off negative energies and bring luck to the wearer. Its enduring presence in ancient cultures underscores its powerful protective symbolism.
Tanzanite represents transformation and new beginnings. Its recent discovery and unique color-changing properties (often displaying different shades of blue and violet under different lights) are seen as metaphors for personal growth and change, making it a powerful stone for those embarking on new life chapters.
Zircon is associated with clarity, wisdom, and a sense of balance. Its brilliant sparkle, often compared to that of a diamond, is believed to enhance mental clarity and spiritual balance, helping the wearer to see truth and wisdom in their life.
Care and Cleaning
The diverse durability of December’s birthstones dictates specific care requirements to ensure their lasting beauty and integrity.
Blue Topaz, due to its high hardness (8) and lack of cleavage, is the most resilient of the four. It can be cleaned with warm, soapy water and a soft brush. It should be protected from prolonged exposure to extreme heat and harsh chemicals, which could damage the stone or its color.
Turquoise requires the most careful handling. Its softness (5–6) and porosity make it vulnerable. It should be cleaned gently with a damp, soft cloth, avoiding any ultrasonic cleaners, steam, or harsh chemicals. It is best to avoid prolonged exposure to lotions, perfumes, and water, as these can cause discoloration or damage over time. Storage should be in a dry, stable environment.
Tanzanite is also considered fragile. While specific cleaning instructions are not provided in the sources, its fragility suggests that gentle cleaning with a soft cloth and mild soap is advisable, avoiding any mechanical or thermal stress.
Zircon, while not detailed in the sources, is generally durable but can be brittle due to its crystal structure. It is best cleaned with warm, soapy water and a soft brush, avoiding sudden temperature changes.
Conclusion
December’s four birthstones—Blue Topaz, Turquoise, Tanzanite, and Zircon—offer a remarkable diversity of color, history, and character. From the ancient protective talisman of turquoise to the modern, transformative elegance of tanzanite, each stone provides a unique connection to the winter season. Their gemological properties range from the exceptionally durable blue topaz, suitable for daily wear, to the more delicate turquoise and tanzanite, which require mindful care. This variety ensures that every December-born individual can find a gemstone that resonates with their personal style, from the vibrant, clear blues of zircon to the soft, earthy tones of turquoise. Ultimately, the wealth of options for December is a celebration of the gemstone world’s diversity, offering a lasting symbol of identity and beauty for those born in the year’s final month.