December is unique among the calendar months, boasting not one, but four recognized birthstones: blue topaz, turquoise, blue zircon, and tanzanite. These gemstones, while united by a predominantly blue color palette reflecting the winter season, each possess distinct histories, geological origins, and symbolic meanings. This article will delve into the characteristics of each of these December birthstones, exploring their historical significance, gemological properties, and the lore surrounding them.
A Quartet of December Gems
For those born in December, the choice of a birthstone is remarkably diverse. While many inquire specifically about a single stone, the tradition allows for selection among blue topaz, turquoise, blue zircon, and tanzanite. This variety provides options to suit individual preferences in color, style, and budget. The common thread uniting these stones is their association with cool, calming blue hues, mirroring the winter landscape.
Historical and Cultural Significance
The history of December’s birthstones spans millennia and encompasses diverse cultures. Turquoise, arguably the oldest of the group, holds a particularly rich past. Ancient Egyptians, pharaohs and rulers included, adorned themselves with turquoise, valuing it for its beauty and perceived protective qualities. Chinese artisans were carving turquoise over 3,000 years ago, demonstrating its early importance in Eastern cultures. Belief in turquoise’s power to guarantee health and good fortune was widespread, and from the 13th century onward, it was thought to safeguard against falls and warn of impending disaster. Hindu mystics believed viewing turquoise after a new moon would bring wealth.
Blue zircon also carries historical weight, though its story is somewhat more complex due to variations in color and treatment. While blue zircon is popular today, historically, zircon appeared in a range of colors, including reddish-brown (jacinth) and colorless, often used as a diamond simulant.
Tanzanite, in contrast, is a relatively recent discovery. Found in the foothills of Mount Kilimanjaro, its introduction to the gem market is a modern phenomenon, adding a contemporary element to the December birthstone selection.
Blue topaz, while topaz itself has a long history, gained prominence as a December birthstone more recently, becoming a popular choice alongside the more traditional turquoise.
Geological Formation and Sources
The origins of these gemstones are as varied as their histories. Turquoise is a secondary mineral, forming in arid regions through the interaction of copper-rich groundwater with aluminum and phosphorus-bearing rocks. It is often found in association with copper deposits.
Zircon forms in igneous rocks and metamorphic rocks, often as a byproduct of magma crystallization. Its varied colors are due to trace elements and, in the case of blue zircon, almost always result from heat treatment.
Tanzanite, a variety of the mineral zoisite, is found in a very limited geographical area – the Merelani Hills of northern Tanzania, near Mount Kilimanjaro. This restricted source contributes to its relative rarity and value.
Blue topaz is typically created through the irradiation of colorless topaz, which itself forms in igneous and metamorphic rocks. Natural blue topaz is rare.
Gemological Properties
Each December birthstone possesses unique gemological characteristics. Turquoise is a semi-translucent to opaque gem, ranging in color from blue to green, often exhibiting matrix – remnants of the host rock. Its hardness on the Mohs scale is relatively low, around 5-6, requiring careful handling.
Blue zircon typically exhibits a hardness of 6.5-7.5 on the Mohs scale. Its refractive index contributes to its brilliance, and the presence of greenish undertones in many blue zircons is a characteristic feature. It’s important to note that zircon can undergo radioactive decay over time, potentially affecting its structure and color, though jewelry typically contains “high zircon” which is more stable.
Tanzanite, with a hardness of 6-7 on the Mohs scale, displays strong trichroism – exhibiting different colors (blue, violet, and burgundy) when viewed from different angles. This pleochroism is a defining characteristic of the gem.
Blue topaz, with a hardness of 8 on the Mohs scale, is a relatively durable gemstone. It is often treated to enhance its color, and its brilliance is notable.
The following table summarizes key gemological properties:
| Gemstone | Chemical Formula | Hardness (Mohs) | Color(s) | Transparency |
|---|---|---|---|---|
| Turquoise | CuAl6(PO4)4(OH)8·4H2O | 5-6 | Blue to Green, often with matrix | Opaque |
| Blue Zircon | ZrSiO4 | 6.5-7.5 | Blue (often with greenish undertones) | Transparent to Translucent |
| Tanzanite | Ca2Al3(SiO4)3(OH) | 6-7 | Blue, Violet, Burgundy | Transparent |
| Blue Topaz | Al2SiO4(OH,F)2 | 8 | Blue | Transparent |
Symbolism and Metaphysical Beliefs
Throughout history, each of these gemstones has been attributed with specific symbolic meanings. Turquoise has long been associated with protection, good fortune, and health. It was believed to ward off negative energy and promote healing.
Blue zircon is often linked to wisdom, prosperity, and honor. It is sometimes believed to promote restful sleep and enhance creativity.
Tanzanite is considered a stone of transformation, facilitating spiritual growth and connecting to higher consciousness. It is also associated with compassion and emotional balance.
Blue topaz symbolizes loyalty, affection, and intellectual pursuits. It is believed to promote communication and inspire creativity.
Care and Cleaning
Proper care is essential to maintain the beauty of December birthstones. Turquoise, due to its relative softness, is susceptible to scratching and should be protected from harsh impacts. It should be cleaned with a soft cloth and mild soap and water. Avoid ultrasonic cleaners and harsh chemicals.
Blue zircon requires gentle cleaning with a soft brush and mild soap and water. Avoid harsh chemicals and ultrasonic cleaners.
Tanzanite is also best cleaned with a soft brush and mild soap and water. Avoid ultrasonic cleaners and steam cleaning, as the heat can damage the stone.
Blue topaz is relatively durable and can be cleaned with warm soapy water and a soft brush. Ultrasonic cleaners are generally safe for untreated blue topaz.
Conclusion
December’s birthstones – blue topaz, turquoise, blue zircon, and tanzanite – represent a captivating array of colors, histories, and symbolic meanings. From the ancient protective powers attributed to turquoise to the modern allure of tanzanite, these gemstones offer a diverse selection for those born in the final month of the year. Each stone embodies elegance, individuality, and a connection to both the natural world and the rich tapestry of human culture. Whether chosen for their aesthetic beauty, historical significance, or perceived metaphysical properties, these December birthstones remain timeless symbols of the season and cherished treasures for generations to come.