December boasts a remarkable array of birthstones, offering a spectrum of blue hues to represent the month. Traditionally, Lapis Lazuli and Turquoise held prominence, while modern lists include Blue Topaz and Tanzanite, with Blue Zircon also recognized as a December birthstone. These gemstones, each with unique origins and characteristics, have captivated cultures for centuries and continue to be cherished in contemporary jewelry. This article will explore the history, geological sources, gemological properties, and symbolism associated with these December birthstones.
History and Lore
The tradition of associating gemstones with specific months dates back to ancient times, with roots in medieval practices. These colored gems were believed to bestow blessings upon those who wore them, particularly when set in rings, pendants, or other jewelry. The practice wasn’t a recent fashion trend, but a deeply ingrained belief system. Lapis Lazuli and Turquoise represent the traditional birthstones for December, each carrying significant historical weight. Lapis Lazuli, with its deep azure tones, was associated with wisdom and royalty in ancient civilizations, considered a stone of truth and enlightenment, believed to enhance intellectual abilities. Turquoise, known for its captivating blue-green hues, has been revered for centuries as a talisman for protection and a symbol of good fortune, instilling a sense of inner calm and fostering creativity.
Blue Topaz, with a history stretching back over two thousand years, was first discovered by the Romans on the Greek Islands of Topazios in the Red Sea. The name “topaz” itself originates from the Sanskrit word for “fire.” While natural blue topaz exists, much of the commercially available material is created by irradiating naturally colorless topaz. The more recent addition of Tanzanite and Blue Zircon to the December birthstone list reflects evolving preferences and discoveries in the gemological world.
Geological Formation and Sources
The origins of these December birthstones are geographically diverse. Blue Topaz is sourced from locations including Texas in the United States, the Ural Mountains in Russia, Brazil, Sri Lanka, Nigeria, and China. Natural blue topaz, however, is relatively rare. Turquoise, as its name suggests, has historical ties to Turkey, though significant deposits are now found in the United States, particularly in the Southwest. Lapis Lazuli is primarily sourced from Afghanistan, though it has also been found in other regions, including Russia and Chile.
Tanzanite is unique in that it is found in only one location: the Merelani Hills of northern Tanzania. This limited source contributes to its relative rarity and value. Blue Zircon is found in various locations, including Sri Lanka, Cambodia, and Australia. The formation of these gemstones varies depending on their geological composition. Topaz, a silicate mineral composed of aluminum and fluorine, forms in igneous rocks. Turquoise is a hydrated phosphate of copper and aluminum, forming in arid regions through secondary enrichment processes. Tanzanite, a calcium aluminum silicate, forms through complex metamorphic processes.
Gemological Properties
Each of December’s birthstones possesses distinct gemological properties. Blue Topaz, with a chemical formula of Al2SiO4(F,OH)4, registers an 8 on the Mohs hardness scale, making it relatively durable, though somewhat brittle. It exhibits a glass-like luster and comes in a range of blue shades, including London Blue (deep inky blue), Swiss Blue (vibrant medium light blue), and Sky Blue (light aqua).
Turquoise is a softer stone, typically ranging from 5 to 6 on the Mohs scale, and is porous, requiring careful handling. Its color is determined by the presence of copper and iron. Lapis Lazuli, also relatively soft (5-6 on the Mohs scale), is composed primarily of lazurite, with varying amounts of calcite, pyrite, and other minerals.
Tanzanite, a calcium aluminum silicate, exhibits a hardness of 6.5 to 7 on the Mohs scale. It is known for its trichroism, displaying different colors (blue, violet, and burgundy) when viewed from different angles. Blue Zircon, with a hardness of 6.5 to 7.5 on the Mohs scale, possesses a high refractive index, contributing to its brilliance.
The following table summarizes key gemological properties:
| Gemstone | Chemical Formula | Hardness (Mohs) | Luster | Color(s) |
|---|---|---|---|---|
| Blue Topaz | Al2SiO4(F,OH)4 | 8 | Glass-like | Deep blue, light blue, sky blue |
| Turquoise | CuAl6(PO4)4(OH)8·4H2O | 5-6 | Waxy | Blue-green |
| Lapis Lazuli | (Na,Ca)9Al6(SiO4)6(SO4,S,Cl)2 | 5-6 | Vitreous | Deep blue |
| Tanzanite | Ca2Al3(SiO4)3(OH) | 6.5-7 | Vitreous | Blue, violet, burgundy (trichroic) |
| Blue Zircon | ZrSiO4 | 6.5-7.5 | Adamantine | Blue |
Symbolism and Metaphysical Beliefs
Beyond their aesthetic appeal, these December birthstones are imbued with symbolic meaning. Blue Topaz is often referred to as the “clarity stone,” believed to stimulate open communication and encourage positive action. It symbolizes opportunity, possibility, wisdom, and success. Some believe it can relieve stress, ease migraines, and soothe sore throats.
Turquoise is associated with protection, good fortune, and inner calm. It is believed to foster creativity and instill a sense of tranquility. Lapis Lazuli, historically linked to wisdom and royalty, is thought to enhance intellectual abilities and stimulate a quest for knowledge. Tanzanite is believed to promote transformation and spiritual growth. Blue Zircon is associated with prosperity and wisdom.
Care and Cleaning
Proper care is essential to maintain the beauty of these December birthstones. Blue Topaz, while relatively hard, is somewhat brittle and should be handled with care to avoid chipping. It can be cleaned with warm, soapy water and a soft brush. Turquoise, being porous, is susceptible to damage from harsh chemicals and should be cleaned gently with a soft cloth and mild soap. Lapis Lazuli should also be cleaned with a soft cloth and mild soap, avoiding abrasive cleaners. Tanzanite is sensitive to heat and should not be exposed to sudden temperature changes. It can be cleaned with warm, soapy water and a soft brush. Blue Zircon requires gentle cleaning with a soft brush and mild soap, avoiding ultrasonic cleaners.
Conclusion
The December birthstones – Blue Topaz, Blue Zircon, Tanzanite, Turquoise, and Lapis Lazuli – represent a rich tapestry of history, geological wonder, and symbolic meaning. From the ancient associations of Lapis Lazuli and Turquoise with wisdom and protection to the modern appeal of Blue Topaz and Tanzanite, these gemstones offer a diverse range of options for those born in December. Each stone possesses unique properties and a captivating allure, making them cherished additions to any jewelry collection and meaningful symbols of the month’s spirit.