December is unique among the months, boasting not one, but three recognized birthstones: Tanzanite, Turquoise, and Zircon. All three gemstones prominently feature shades of blue, reflecting the cool tones of the winter season, though each possesses distinct characteristics, histories, and symbolic meanings. This article will delve into the geological origins, historical significance, gemological properties, and care of these captivating December birthstones.
A Trio of Blues: Historical Significance and Lore
The association of gemstones with specific months and their corresponding astrological signs dates back to ancient times. Originally, these “zodiac stones” were considered one and the same as birthstones, linking individuals to the cosmos through the power of gems. While the modern distinction between zodiac and birthstones exists, the tradition of assigning meaning to gemstones remains strong.
Turquoise holds the longest documented history of the three. As early as 5500 BCE, ancient Egyptians mined turquoise in the Sinai region, referring to it as “mefkat,” meaning “joy” and “delight.” The stone held significant cultural and religious importance, adorning pharaohs and symbolizing health and good fortune. Chinese artisans were carving turquoise over 3,000 years ago. From the 13th century onward, it was believed to offer protection from falls, particularly while riding horses, and to warn of impending disaster by fracturing. Hindu mystics believed viewing turquoise after a new moon would bring great wealth. The name “turquoise” itself originated in the 13th century, stemming from the French expression “pierre tourques,” meaning “Turkish stone,” as the gem often entered Europe through Turkish trade routes. It was officially recognized as a December birthstone by the American National Association of Jewelers in 1912.
Zircon’s history is equally rich, though its origins are debated. Some scholars believe the name derives from the Arabic word “zarkun,” meaning “cinnabar” or “vermilion,” while others suggest a Persian origin, “zargun,” meaning “gold colored.” This etymological ambiguity reflects the gem’s diverse color range, encompassing red, orange, yellow, brown, green, and blue. During the Middle Ages, zircon was thought to induce sleep and ward off evil spirits. In Hindu tradition, it alternates with hessonite garnet as one of the nine gems of the navaratna, believed to bestow wealth, wisdom, and good health upon the wearer. Victorian-era jewelers favored blue zircon, with fine specimens appearing in English estate jewelry from the 1880s.
Tanzanite, in contrast, is a relatively recent discovery. It was not until the 1960s that this gem was recognized, initially named “Blue Zoisite” before being officially renamed Tanzanite in honor of its country of origin, Tanzania. Its deep blue-violet hue quickly gained popularity, establishing it as a significant December birthstone.
Geological Formation and Sources
Turquoise is a semi-translucent to opaque gem, its color derived from the presence of copper, aluminum, zinc, and iron. Iron imparts a greenish hue, while zinc contributes to a yellowish tone. The most prized color is often described as “Robin’s Egg Blue,” “Sky Blue,” or “Persian Blue.” Turquoise forms in relatively dry, arid environments, often in association with copper deposits. Significant sources include Iran, China, Mexico, the Middle East, Kazakhstan, and the United States of America.
Zircon is found in a variety of geological settings, often near sapphire deposits. Major sources include Sri Lanka, Australia, Myanmar, Vietnam, and Cambodia. The gem’s broad color palette is a result of trace elements within its crystal structure. Colorless zircon is particularly prized for its brilliance and “fire,” the flashes of multicolored light it exhibits.
Tanzanite is exclusively found in a small area near the Mererani Hills of northern Tanzania. This limited geographical source contributes to its rarity and value. The gem is a variety of the mineral zoisite, and its unique blue-violet color is due to the presence of vanadium.
Gemological Properties
Here's a comparative table of key gemological properties:
| Gemstone | Chemical Formula | Color(s) | Hardness (Mohs) | Transparency |
|---|---|---|---|---|
| Turquoise | CuAl6(PO4)4(OH)8·4H2O | Blue to Green | 5-6 | Opaque |
| Zircon | ZrSiO4 | Red, Orange, Yellow, Brown, Green, Blue | 6-7.5 | Transparent to Opaque |
| Tanzanite | Ca2Al3(SiO4)3(OH) | Blue, Violet, Purple | 6-7 | Transparent |
Turquoise’s color can change over time due to absorption of body oils and moisture, highlighting the importance of proper care. Zircon exhibits strong pleochroism, meaning it displays different colors when viewed from different angles. Tanzanite is also known for its pleochroism, showcasing varying shades of blue, violet, and red. This phenomenon contributes to its captivating brilliance. Zircon can be heat treated to enhance or alter its color, producing blue and colorless varieties, as well as orange, yellow, and red hues. Some heat-treated zircon may revert to its original color with prolonged exposure to bright light.
Symbolism and Metaphysical Beliefs
Throughout history, each of these December birthstones has been attributed with various symbolic meanings and metaphysical properties. Turquoise has long been associated with protection, good fortune, and joy. It was believed to safeguard against falls and warn of impending danger.
Zircon was thought to promote restful sleep and ward off evil spirits. In Hindu tradition, it is considered a source of wealth, wisdom, and good health when combined with other navaratna gems.
Tanzanite, while newer to the world of gemstone lore, is often associated with wisdom, peace, and inner strength. Its vibrant color is believed to inspire confidence and facilitate communication.
Care and Cleaning
Proper care is essential to maintain the beauty of these December birthstones. Turquoise, being relatively soft, is susceptible to scratches and abrasions. Avoid wearing it during strenuous activities and clean it gently with warm, soapy water.
Zircon, with a hardness of 6-7.5, is more durable but should still be protected from harsh conditions. Avoid wearing it while gardening, playing sports, or doing dishes. Clean it with a soft brush and mild soap in warm water. Ultrasonic and steam cleaners are not recommended. Some heat-treated zircon may experience color changes with prolonged light exposure.
Tanzanite, also with a hardness of 6-7, requires gentle handling. Warm, soapy water is the best cleaning method. Ultrasonic and steam cleaners should be avoided, as they can damage the gem.
Conclusion
December’s birthstones – Tanzanite, Turquoise, and Zircon – offer a diverse range of colors, histories, and symbolic meanings. From the ancient origins of turquoise to the recent discovery of tanzanite, each gem holds a unique place in the world of gemstones. Whether chosen for their aesthetic beauty, historical significance, or perceived metaphysical properties, these blue-hued gems provide a captivating connection to the winter season and the individuals born within it.