December is unique among the calendar months, boasting not one, but four recognized birthstones: turquoise, zircon, blue topaz, and tanzanite. While turquoise holds the longest history as a December gem, the latter three have been added to the list in more recent times, offering a diverse palette of blues and a range of symbolic meanings for those born in the final month of the year. This article will explore the history, geological origins, gemological properties, and cultural significance of each of these captivating gemstones.
A History of December Birthstones
The association of gemstones with specific months dates back centuries, with early traditions often varying across cultures. Ruby was once linked to December in ancient times, believed to sharpen the mind and encourage affection. Chrysoprase, the old Russian birthstone for December, was thought to bring good fortune and heal emotional wounds. Similarly, onyx held significance as the Tibetan birthstone, offering self-mastery and protection, while bloodstone was a traditional choice, representing courage and vitality.
However, the modern selection of December birthstones began to solidify in the 20th century. Turquoise has a long and storied past, with evidence of its use dating back thousands of years. Ancient Egyptians, including the pharaohs, prized turquoise, as evidenced by its inclusion in the funerary mask of Tutankhamun. Ancient Chinese artisans also incorporated turquoise into their designs over 3,000 years ago. The name “turquoise” itself is relatively recent, originating from the French term “turquois,” meaning “Turkish,” as the gem was initially brought to Europe from Turkey. Egyptians referred to it as “mefkat,” signifying both “joy” and “delight.”
Zircon gained recognition as a December birthstone after 1952, replacing lapis lazuli, which was previously associated with the month. Blue zircon is the most commonly recognized variety for December, though zircon occurs in a spectrum of colors. Tanzanite was added to the list in 2002, a relatively recent discovery that quickly gained popularity. Blue topaz, while not always listed among the traditional three, is also frequently considered a December birthstone.
Geological Formation and Sources
The origins of these December birthstones are geographically diverse. Turquoise forms in relatively dry, arid regions, typically in the vicinity of copper deposits. It is a secondary mineral, meaning it forms as a result of alteration of other minerals. Significant sources of turquoise include the United States, Iran, and China.
Zircon is a widespread mineral found in igneous, metamorphic, and sedimentary rocks. It forms under a variety of geological conditions and is sourced from locations such as Cambodia, Sri Lanka, and Australia. Blue zircon, the most popular variety for December, gets its color from trace amounts of elements within its crystal structure.
Blue topaz is often created through irradiation of colorless topaz, which is found in Brazil, Nigeria, and Russia. Natural blue topaz is rarer. Tanzanite, a relatively recent discovery, is found exclusively in the Merelani Hills of northern Tanzania, near Mount Kilimanjaro. It is a trichroic gemstone, meaning it displays three different colors – blue, violet, and burgundy – depending on the viewing angle.
Gemological Properties
Each of December’s birthstones possesses unique gemological properties.
Turquoise: Turquoise is a hydrated copper aluminum phosphate with a hardness of 5-6 on the Mohs scale. Its color ranges from sky blue to greenish-blue, often with matrix (veins of the host rock) visible within the stone.
Blue Zircon: Zircon has a chemical formula of ZrSiO4 and a hardness of 6.5-7.5 on the Mohs scale. Blue zircon’s color is derived from trace amounts of elements. It exhibits strong double refraction, which can give it a slightly blurred appearance.
Blue Topaz: Topaz has a chemical formula of Al2SiO4(OH,F)2 and a hardness of 8 on the Mohs scale. Blue topaz is often created by irradiating colorless topaz, enhancing its color. It exhibits a vitreous luster and is relatively resistant to abrasion.
Tanzanite: Tanzanite is a calcium aluminum silicate with a hardness of 6.5-7 on the Mohs scale. Its trichroism is a defining characteristic, displaying blue, violet, and burgundy hues. It is relatively pleochroic, meaning it shows different colors when viewed from different directions.
The following table summarizes these properties:
| Gemstone | Chemical Formula | Hardness (Mohs) | Color(s) |
|---|---|---|---|
| Turquoise | CuAl6(PO4)4(OH)8·4H2O | 5-6 | Sky blue to greenish-blue |
| Blue Zircon | ZrSiO4 | 6.5-7.5 | Blue |
| Blue Topaz | Al2SiO4(OH,F)2 | 8 | Blue |
| Tanzanite | Ca2Al3(SiO4)3(OH) | 6.5-7 | Blue, violet, burgundy |
Symbolism and Metaphysical Beliefs
Throughout history, these gemstones have been attributed with various symbolic meanings and metaphysical properties. Turquoise has long been considered a protective stone, believed to ward off negative energy and bring good fortune. It was associated with joy and delight in ancient Egypt.
Blue zircon is thought to promote emotional balance and encourage joy. Blue topaz is believed to stimulate self-esteem and facilitate learning, aiding in navigating complex ideas. It is also considered a calming stone, connecting individuals to spiritual sources and enhancing meditation. Tanzanite is regarded as a protective and soothing stone, facilitating the sharing of spiritual insights with calmness and clarity.
Historically, ruby, once associated with December, symbolized passion, protection, and prosperity. Chrysoprase was believed to bring good luck and mend broken hearts, while onyx offered self-mastery and protective energy.
Care and Cleaning
Proper care is essential to maintain the beauty of December birthstones. Turquoise is relatively soft and porous, requiring gentle cleaning with a soft cloth and mild soap. Avoid harsh chemicals and ultrasonic cleaners. Zircon, topaz, and tanzanite are more durable but should still be handled with care. Cleaning can be done with warm, soapy water and a soft brush. Avoid sudden temperature changes, as this can cause fractures. Regular cleaning and mindful handling will ensure these gemstones retain their brilliance for years to come. Bathing the stones in full moonlight is also suggested for energizing them, and cleansing with sage or selenite is recommended.
Conclusion
December’s birthstones – turquoise, zircon, blue topaz, and tanzanite – represent a captivating array of colors, histories, and symbolic meanings. From the ancient origins of turquoise to the modern discovery of tanzanite, each gem offers a unique connection to the past and a source of beauty and inspiration. Whether chosen for their aesthetic appeal, their perceived metaphysical properties, or their personal significance, these gemstones embody the spirit of December and provide a meaningful way to celebrate those born in this enchanting month.