December is a unique month in the world of gemstones, offering not one, but four recognized birthstones: blue topaz, turquoise, tanzanite, and zircon. While blue topaz is frequently cited as the modern December birthstone, the historical and traditional choices – turquoise and zircon – continue to hold significance, alongside the more recently discovered tanzanite. This article will delve into the history, geological origins, gemological properties, and symbolism of these captivating December birthstones, providing a comprehensive overview for enthusiasts and those seeking to understand their unique qualities.
A History of December’s Gems
The tradition of associating specific gemstones with each month has evolved over time. Originally, multiple stones were linked to each month, often based on astrological signs or ancient beliefs. Over the 20th century, a standardization occurred, leading to the modern birthstone chart. December’s selection reflects this evolution, with turquoise and zircon representing older traditions, while tanzanite, discovered in 1967, and blue topaz represent more recent additions.
Turquoise boasts the longest history of the December birthstones, with evidence of its use dating back to 3000 BCE. Ancient civilizations, including those in Egypt and Persia, highly valued turquoise for its vibrant color and believed it possessed protective powers. Zircon, too, is an ancient mineral, symbolizing wisdom and prosperity. Tanzanite, as a more recent discovery, lacks the extensive historical lore of its counterparts, but has quickly gained prominence due to its striking beauty and rarity.
Geological Formation and Sources
Each of these December birthstones originates from distinct geological processes and is found in specific locations around the globe.
Blue topaz is commonly found in Brazil, Nigeria, Sri Lanka, and China, with Brazil being the largest producer. Turquoise is mined in the southwestern United States, particularly in Arizona and Nevada, as well as in Iran (where it is known as Persian turquoise) and China. Tanzanite is exceptionally unique, found exclusively in the Merelani Hills of northern Tanzania, near Mount Kilimanjaro. Zircon sources include Sri Lanka, Cambodia, Myanmar, and Australia. The geographic diversity of these gemstones contributes to their individual allure and market value.
Gemological Properties
The four December birthstones exhibit a range of gemological properties, influencing their appearance, durability, and suitability for various jewelry applications.
Blue Topaz: This silicate mineral registers 8 on the Mohs scale of hardness, making it relatively durable and suitable for everyday wear. It is often heat-treated to enhance its blue coloration.
Turquoise: A hydrated phosphate of copper and aluminum, turquoise typically ranges from 5 to 6 on the Mohs scale. Its color varies from sky blue to greenish-blue, depending on the presence of other minerals.
Tanzanite: A blue-violet variety of the mineral zoisite, tanzanite possesses a hardness of 6.5 to 7 on the Mohs scale. Its pleochroism – displaying different colors when viewed from different angles – is a notable characteristic.
Zircon: Ranging from 6 to 7.5 on the Mohs scale, zircon’s color can vary significantly, including blue, colorless, orange, yellow, and red. It is commonly heat-treated to produce blue and colorless varieties. Prolonged exposure to bright light can sometimes cause heat-treated zircon to revert to its original color.
The following table summarizes these properties:
| Gemstone | Chemical Composition | Hardness (Mohs) | Color(s) |
|---|---|---|---|
| Blue Topaz | Al₂SiO₄(OH,F)₂ | 8 | Blue |
| Turquoise | CuAl₆(PO₄)₄(OH)₈·4H₂O | 5-6 | Sky blue to greenish-blue |
| Tanzanite | Ca₂Al₃(SiO₄)₃(OH) | 6.5-7 | Blue-violet |
| Zircon | ZrSiO₄ | 6-7.5 | Blue, colorless, orange, red |
Symbolism and Metaphysical Beliefs
Throughout history, each of these gemstones has been attributed with specific meanings and powers. Turquoise, with its ancient roots, symbolizes peace, health, and good fortune. Zircon is believed to represent wisdom and prosperity. Tanzanite, though a more recent discovery, is associated with insight and spiritual awakening. Blue topaz is often linked to clear communication and emotional stability.
While these beliefs are not scientifically proven, they contribute to the enduring appeal of these gemstones and their significance as birthstones. The choice of a particular December birthstone can therefore be a personal one, reflecting individual values and aspirations.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of December birthstones. Due to its higher hardness, blue topaz is relatively durable and can withstand regular wear. Turquoise, being softer, requires more gentle handling and should be protected from impacts. Tanzanite and zircon, with moderate hardness, should also be worn with care.
Cleaning these gemstones generally involves using a soft brush and mild soap in warm water. Ultrasonic and steam cleaners are not recommended for zircon. Exposure to heat can alter the color of some zircon varieties, so it should be stored away from direct sunlight or heat sources. It is best to avoid wearing zircon in rough conditions, such as during gardening or sports.
Choosing a December Birthstone
With four options available, selecting a December birthstone can be a delightful experience. Blue topaz offers a durable and affordable choice for everyday wear. Turquoise provides a connection to ancient traditions and a unique, earthy aesthetic. Tanzanite presents a rare and captivating gem for special occasions. Zircon, with its diverse color range and historical significance, offers a versatile option for those seeking a timeless gemstone.
Ultimately, the best December birthstone is the one that resonates most with the individual, whether based on its aesthetic appeal, symbolic meaning, or personal connection.
Conclusion
December’s birthstones – blue topaz, turquoise, tanzanite, and zircon – represent a diverse and captivating collection of gemstones. From the ancient lore surrounding turquoise and zircon to the modern appeal of blue topaz and the recent discovery of tanzanite, each stone offers a unique blend of history, beauty, and symbolism. Understanding their geological origins, gemological properties, and care requirements allows for a deeper appreciation of these remarkable gifts from the earth. Whether chosen for their aesthetic qualities, metaphysical beliefs, or personal significance, these December birthstones continue to enchant and inspire.