December is unique among the calendar months, boasting not one, but four recognized birthstones: turquoise, zircon, tanzanite, and blue topaz. This abundance offers a wide range of options for those seeking a gemstone with special significance, varying considerably in price, origin, and aesthetic qualities. While blue is often considered the color most associated with December’s birthstones, the choices extend beyond a single hue and encompass a rich history and diverse symbolism.
A Quartet of Choices: Historical Context and Discovery
The tradition of associating specific gemstones with each month evolved over time. Initially, only a single stone represented each birth month, often based on historical or astrological associations. Turquoise and zircon were among the earliest choices for December, reflecting their long-standing presence in jewelry and cultural practices. Blue topaz was added later as a more affordable and readily available alternative. The most recent addition, in 2002, was tanzanite, a gemstone discovered relatively recently and quickly gaining popularity for its exceptional beauty and rarity.
The story of tanzanite is particularly compelling. Discovered in 1967 in the Merelani Hills of northern Tanzania, it remained largely unknown until 1968 when Tiffany & Co. recognized its potential and introduced it to the market, naming it after its country of origin. Remarkably, Tanzania remains the only source of tanzanite globally, contributing to its value and exclusivity.
Gemological Properties and Characteristics
Each of December’s birthstones possesses distinct gemological properties. Blue topaz, a variety of the silicate mineral topaz, is available in a range of blue shades, from pale sky blue to deep London blue. Its hardness is 8 on the Mohs scale, making it a relatively durable gemstone suitable for everyday wear.
Zircon, often mistaken for diamond due to its brilliance, is a zirconium silicate. It exhibits a high refractive index, contributing to its fire and sparkle. Zircon can occur in a variety of colors, including brown, red, yellow, and green, but the blue varieties are most commonly associated with December. Its hardness is 6.5-7.5 on the Mohs scale.
Turquoise, a hydrated phosphate of copper and aluminum, is known for its distinctive opaque blue-green color. The color is influenced by the presence of copper and iron. Turquoise is relatively soft, with a hardness of 5-6 on the Mohs scale, and requires careful handling.
Tanzanite, a variety of the mineral zoisite, is prized for its trichroism – the ability to display different colors depending on the viewing angle. Typically exhibiting violetish blue to bluish violet hues, the most valuable tanzanites display a strong, saturated blue color. Its hardness is 6.5-7 on the Mohs scale. The color of tanzanite is often enhanced through heat treatment, a common practice in the industry.
The following table summarizes key properties:
| Gemstone | Chemical Composition | Hardness (Mohs) | Color(s) |
|---|---|---|---|
| Topaz | Al₂SiO₄(OH,F)₂ | 8 | Blue, Yellow, Pink, Clear |
| Zircon | ZrSiO₄ | 6.5-7.5 | Blue, Brown, Red, Yellow, Green |
| Turquoise | CuAl₆(PO₄)₄(OH)₈·4H₂O | 5-6 | Blue-Green |
| Tanzanite | Ca₂Al₃(SiO₄)₃(OH) | 6.5-7 | Violetish Blue to Bluish Violet |
Value and Market Considerations
The value of December birthstones varies significantly. Citrine and amethyst are generally the most affordable, valued between $10 and $400 per carat. Topaz and tourmaline fall into a similar price range. However, tanzanite, ruby, emerald, and sapphire command significantly higher prices.
Diamonds, rubies, and emeralds are considered the rarest and most valuable birthstones, with diamonds ranging from $3,000 to $11,000 per carat, rubies from $3,000 to $10,000 per carat, and emeralds from $3,000 to $7,000 per carat. Sapphires are valued between $1,000 and $3,500 per carat.
Tanzanite can reach up to $1,500 per carat for high-quality stones exceeding five carats. The depth of color saturation is a primary factor influencing its value, with deeper blues commanding higher prices. The quality of the cut is also crucial, as it affects the gemstone’s brilliance and color reflection. In March 2024, a 703.4-carat tanzanite sculpture, named L’Heure Bleu, broke records as the largest cut tanzanite.
Symbolism and Metaphysical Beliefs
Throughout history, gemstones have been imbued with symbolic meanings and believed to possess metaphysical properties. Turquoise has long been associated with protection, healing, and good fortune, particularly in Native American cultures. Zircon has been linked to prosperity and wisdom. Topaz symbolizes love, affection, and strength. Tanzanite, a more recent addition to the birthstone list, is believed to promote spiritual awareness and transformation.
Care and Maintenance
The care required for each December birthstone varies based on its hardness and durability. Topaz, with its relatively high hardness, is generally resistant to scratching and can be cleaned with warm soapy water and a soft brush. Zircon, while brilliant, is more susceptible to abrasion and should be handled with care. Turquoise, being a softer stone, requires gentle cleaning and should avoid harsh chemicals or ultrasonic cleaners. Tanzanite, also relatively soft, should be protected from scratches and sudden temperature changes.
Some jewelers advise against setting topaz as a center stone due to its physical properties, but it can be beautifully incorporated as a side stone.
Choosing the Right December Birthstone
The choice of a December birthstone is ultimately a matter of personal preference. For those seeking a durable and affordable option, blue topaz is an excellent choice. Zircon offers exceptional brilliance, while turquoise provides a unique and culturally significant option. Tanzanite, with its rarity and captivating color, represents a more luxurious and exclusive choice. Considering personal style, budget, and the desired symbolism can guide the selection process.
Conclusion
December’s four birthstones – turquoise, zircon, tanzanite, and blue topaz – offer a diverse range of options for those born in the final month of the year. From the ancient heritage of turquoise to the modern discovery of tanzanite, each gemstone carries its own unique history, symbolism, and gemological properties. Understanding these characteristics allows for a more informed and meaningful selection, whether as a personal adornment or a thoughtful gift. The variety ensures that there is a December birthstone to suit every taste and budget, celebrating the individuality of those born under its winter skies.