December boasts a unique distinction among the months: it has not one, but three recognized birthstones – zircon, tanzanite, and blue topaz. Each gem offers a distinct allure, history, and set of properties, providing a diverse range of options for those born in the final month of the year. This article will delve into the origins, characteristics, and significance of these December birthstones, drawing upon available knowledge to provide a comprehensive overview.
A History of December Birthstones
Historically, turquoise and lapis lazuli were associated with December, as indicated by traditional birthstone charts. However, the modern list, evolving over time, has expanded to include zircon, tanzanite (added in 2002), and blue topaz. The inclusion of these gems reflects both evolving gemological understanding and market preferences. Zircon, with its long and varied history, has been valued for centuries, while tanzanite is a relatively recent discovery, gaining prominence in the late 20th century. Blue topaz, a variety of topaz, has also become increasingly popular as a December birthstone.
Zircon: A Gem of Fire and Confusion
The very name “zircon” has a debated origin. Some scholars trace it to the Arabic word zarkun, meaning “cinnabar” or “vermilion,” referencing the red varieties of the gem. Others suggest a Persian root, zargun, translating to “gold colored,” acknowledging the gem’s broader color range. This range encompasses red, orange, yellow, brown, green, and blue, making either etymological origin plausible.
Throughout history, zircon has often been mistaken for diamond due to its brilliance and strong “fire” – the flashes of multicolored light it exhibits. During the Middle Ages, zircon was believed to induce sleep and ward off evil spirits. In Hindu tradition, zircon alternates with hessonite garnet as one of the nine gems of the navaratna, believed to bestow wealth, wisdom, and good health upon the wearer when combined with the other eight gems. Victorian-era jewelry frequently featured blue zircon, particularly in English estate pieces from the 1880s. It is important to note that zircon is often confused with cubic zirconia, a lab-created diamond simulant, due to their similar appearance.
Tanzanite: A Modern Marvel
Tanzanite is the newest addition to the December birthstone family, officially recognized in 2002. Its discovery is relatively recent, and its captivating blue to violet hues are achieved through heat treatment of brownish zoisite. This heat treatment is a standard practice that permanently enhances the color, reducing red and yellow tones to reveal the desired blue and violet shades.
The Maasai people of Tanzania have a legend surrounding the gem’s origin, claiming that a bolt of lightning struck the ground, transforming the rocks into shimmering blue stones. They traditionally gift tanzanite to mothers after childbirth, symbolizing health, well-being, and prosperity. Historically, tanzanite was believed to strengthen the immune system, detoxify blood, and regenerate cells.
Blue Topaz: A Stone of Fire and the Sea
The origin of the name “topaz” is also subject to debate. Some believe it derives from the Sanskrit word Tapas, meaning “fire,” while others attribute it to the Greek word Topazos, the name of an island in the Red Sea. Regardless of its etymological roots, topaz has long been associated with warmth and brilliance. Blue topaz, specifically, has gained popularity as a December birthstone, offering a vibrant and accessible alternative to other gems.
Geological Formation and Sources
Zircon is found in a variety of geological settings, including igneous, metamorphic, and sedimentary rocks. Significant sources include Sri Lanka, Cambodia, Thailand, and Australia. Tanzanite, however, is exceptionally rare and found in only one location: the Merelani Hills of northern Tanzania. This limited source contributes to its value and exclusivity. Blue topaz is commonly produced by irradiating colorless topaz, which is found in Brazil, Nigeria, and Russia.
Gemological Properties
The following table summarizes the key gemological properties of the three December birthstones:
| Property | Zircon | Tanzanite | Blue Topaz |
|---|---|---|---|
| Chemical Formula | ZrSiO₄ | Ca₂Al₃(SiO₄)₃(OH) | Al₂SiO₄(OH,F)₂ |
| Color | Red, Orange, Yellow, Brown, Green, Blue, Colorless | Blue, Violet | Blue |
| Hardness (Mohs) | 6.5 - 7.5 | 6 - 7 | 8 |
| Refractive Index | 1.810 - 2.024 | 1.619 - 1.662 | 1.609 - 1.625 |
| Specific Gravity | 3.93 - 4.73 | 3.35 - 3.50 | 3.49 - 3.57 |
Zircon’s hardness ranges from 6.5 to 7.5 on the Mohs scale, making it relatively durable but susceptible to abrasion. Tanzanite, with a hardness of 6-7, is softer and requires more careful handling. Blue topaz is significantly harder, registering 8 on the Mohs scale, making it more resistant to scratching.
Symbolism and Metaphysical Beliefs
Each of these December birthstones carries its own set of symbolic meanings. Zircon has been associated with prosperity, wisdom, and protection. Tanzanite is linked to transformation, intuition, and spiritual growth. Blue topaz is believed to promote communication, courage, and emotional balance.
Tanzanite, in particular, is associated with rarity and new beginnings. It was historically believed to strengthen the immune system and promote cellular regeneration. Zircon, in Hindu tradition, is part of a set of nine gems believed to bring overall well-being.
Care and Cleaning
Proper care is essential to maintain the beauty of these December birthstones. Zircon should be handled with care to avoid sharp impacts and cleaned with mild soap and warm water. Ultrasonic and steam cleaners are not recommended. Tanzanite, being relatively soft, should also be protected from scratches and sudden temperature changes. It is best cleaned with warm, soapy water and should not be subjected to ultrasonic or steam cleaning. Blue topaz, due to its hardness, is more durable but should still be cleaned with mild soap and warm water to avoid damaging any surface coatings. All three stones should be stored separately from other jewelry to prevent scratching.
Conclusion
Zircon, tanzanite, and blue topaz each offer a unique and compelling choice for those seeking a December birthstone. From the ancient lore surrounding zircon to the modern allure of tanzanite and the vibrant beauty of blue topaz, these gems represent a diverse range of history, symbolism, and gemological properties. Understanding these characteristics allows for informed selection and proper care, ensuring that these December birthstones continue to sparkle for generations to come.