December boasts a remarkable array of birthstones – blue topaz, blue zircon, tanzanite, and turquoise – offering a spectrum of blues to suit every preference. Historically, turquoise held the sole designation, but additions throughout the 20th century have expanded the choices, providing a diverse range of options in terms of color, sparkle, and price. Each of these gemstones carries its own unique history, symbolism, and geological origins, making December a particularly rich month for gemstone lore.
A History of Choice
For many years, turquoise was the undisputed birthstone of December. Its history stretches back millennia, with evidence of its use in ancient Egypt, where pharaohs adorned themselves with the stone, and in China, where artisans carved it over 3,000 years ago. The name “turquoise” itself originates from the French “pierre tourques,” meaning “Turkish stone,” reflecting the belief that the gem arrived in Europe via Turkish traders.
However, the 20th century saw the introduction of alternatives. Blue zircon was added to appeal to those seeking a more brilliant sparkle than turquoise could provide. Later, in 1967, the discovery of tanzanite in Tanzania prompted jewelers to advocate for its inclusion, which was officially recognized by the Gemological Institute of America (GIA) in 2002. Finally, blue topaz joined the ranks in 2016, offering an affordable and durable option. Today, the GIA acknowledges all four as December birthstones, resulting in the broadest range of birthstone colors for any single month.
Geological Origins and Sources
The origins of these December birthstones are as diverse as their colors. Turquoise, a semi-translucent to opaque gem, forms in relatively dry, arid environments, often in the vicinity of copper deposits. Its color arises from the presence of copper, while aluminum and other minerals contribute to its structure.
Blue topaz, a popular modern choice, is a variety of the mineral topaz that has been treated to enhance its blue color. Topaz is found in igneous and metamorphic rocks and is sourced from various locations worldwide.
Tanzanite, a relatively recent discovery, is found exclusively in the Merelani Hills of Tanzania. This unique geological setting is crucial to its formation, and its limited source contributes to its value.
Blue zircon, known for its brilliance, is a variety of the mineral zircon. Zircon is found in a variety of geological settings, including igneous, metamorphic, and sedimentary rocks.
Gemological Properties
Each December birthstone possesses distinct gemological properties. Turquoise is relatively soft, with a Mohs hardness of around 5-6, making it susceptible to scratching. It is often characterized by the presence of matrix, which are remnants of the host rock within the gemstone.
Blue topaz boasts a Mohs hardness of 8, making it a durable gemstone suitable for everyday wear. Its color ranges from pale sky blue to deep London blue, depending on the treatment and origin.
Tanzanite exhibits a Mohs hardness of 6.5 to 7, making it moderately durable. It is known for its trichroism, meaning it displays three different colors – blue, violet, and burgundy – depending on the viewing angle.
Blue zircon also has a Mohs hardness of 6.5 to 7.5, and is prized for its high refractive index, which contributes to its exceptional brilliance and fire. Zircon can exhibit a range of colors, including blue, and is sometimes heat-treated to enhance its color.
Here's a table summarizing the key properties:
| Gemstone | Mohs Hardness | Color(s) | Notable Features |
|---|---|---|---|
| Turquoise | 5-6 | Blue to Green | Often contains matrix |
| Blue Topaz | 8 | Pale to Deep Blue | Durable, various shades |
| Tanzanite | 6.5-7 | Blue, Violet, Burgundy | Trichroic |
| Blue Zircon | 6.5-7.5 | Blue | High brilliance |
Symbolism and Metaphysical Beliefs
Throughout history, these gemstones have been imbued with symbolic meaning and metaphysical properties. Turquoise has long been associated with protection, health, and good fortune. Ancient Egyptians believed it offered protection, while Hindu mystics thought it brought wealth. It was even believed to prevent falls, particularly from horses, and to warn of impending disaster by breaking into pieces.
Blue topaz is believed to promote good communication, calm the mind, and provide restful sleep. It was historically given to those with hot tempers or fevers, thought to have a cooling effect.
Tanzanite is often associated with transformation, intuition, and spiritual growth. Its vibrant color is said to inspire creativity and enhance psychic abilities.
Blue zircon is believed to promote wisdom, honor, and prosperity. It is also thought to enhance clarity of thought and emotional balance.
Care and Cleaning
Proper care is essential to maintain the beauty of these December birthstones. Turquoise, being relatively soft, requires gentle handling and should be protected from scratches and harsh chemicals. Cleaning can be done with a soft cloth and mild soapy water.
Blue topaz, with its higher hardness, is more durable and can be cleaned with warm soapy water and a soft brush. Avoid ultrasonic cleaners, as they may damage the stone.
Tanzanite is also best cleaned with warm soapy water and a soft brush. Avoid harsh chemicals and ultrasonic cleaners.
Blue zircon should be cleaned similarly to topaz and tanzanite, with warm soapy water and a soft brush. Due to its potential for brittleness, avoid sudden temperature changes.
Alternative Birthstones and Zodiac Associations
While blue topaz, blue zircon, tanzanite, and turquoise are the primary December birthstones, alternative options exist. Some traditions associate other gemstones with the month of December, based on astrological signs or other criteria. For example, some sources link Sagittarius (November 23 - December 22) with topaz, while Capricorn (December 23 - January 20) is associated with ruby. Alternative birthstones can also be chosen based on the day of the week or the hour of birth, offering a highly personalized selection.
Conclusion
The December birthstones – blue topaz, blue zircon, tanzanite, and turquoise – represent a captivating spectrum of color, history, and symbolism. From the ancient origins of turquoise to the modern discovery of tanzanite, each gemstone offers a unique story and a connection to the rich tapestry of gemological lore. Whether seeking protection, tranquility, inspiration, or simply a beautiful adornment, the December birthstones provide a wealth of choices for those born in the final month of the year.