The final month of the year, December, is uniquely associated with three distinct and captivating gemstones: Turquoise, Zircon, and Tanzanite. Each of these stones carries its own rich history, geological origin, and set of symbolic meanings, offering a diverse palette for those born in the winter month. While the provided sources focus primarily on general December facts and traditions, they consistently identify these three minerals as the official birthstones for the month. This article will delve into the available information regarding each gemstone, exploring their origins, cultural significance, and the reasons they have been chosen to represent December.
History and Lore of December's Gems
The tradition of assigning specific stones to months is a modern convention, but the history of these particular gemstones stretches back millennia. The sources indicate that the practice of associating gemstones with birth months evolved over time, with December's stones being a relatively recent consolidation.
Turquoise is perhaps the oldest of the three, with a history spanning thousands of years. It has been prized by ancient civilizations across the globe, from the Egyptians and Persians to the Native Americans of the Southwest United States. The sources note that Turquoise is "believed to bring good fortune and protection," a belief that has persisted through centuries. Its name is derived from the French "pierre turquoise," meaning "Turkish stone," as it was brought to Europe from Persia via Turkey. Historically, it was worn as an amulet to ward off evil and protect the wearer from harm. Its sky-blue to greenish-blue color, reminiscent of water and sky, contributed to its association with protection and tranquility. While the sources do not provide a detailed history of Turquoise's discovery, its inclusion as a December birthstone is firmly established in modern tradition.
Zircon has a more complex history, often confused with the synthetic diamond simulant cubic zirconia. However, natural zircon is one of the oldest minerals on Earth, with crystals found in sediments that are billions of years old. The sources mention that Zircon "comes in a variety of colors but is most popular in its blue form." This blue variety, often heat-treated to enhance its color, has been used in jewelry for centuries. In the Middle Ages, zircon was believed to induce sleep, promote prosperity, and ward off evil spirits. Its high refractive index and strong dispersion (fire) give it a brilliance that rivals diamond, making it a prized gemstone in its own right. The historical lore surrounding zircon is rich, though the provided sources primarily focus on its modern status as a birthstone.
Tanzanite is the newest addition to the December birthstone family. The sources clearly state that Tanzanite "was discovered in Tanzania in 1967 and is rarer than diamonds." This specific discovery date and location are consistently reported across the sources. Its rapid rise to prominence is a testament to its unique beauty. Before its discovery, the only significant source of the mineral zoisite was in Norway, but the vibrant blue-violet variety found near Mount Kilimanjaro was unprecedented. Its rarity, combined with its striking trichroic nature (showing different colors when viewed from different angles), made it an instant sensation in the gem world. The sources highlight its rarity as a key characteristic, distinguishing it from the more historically entrenched Turquoise and Zircon.
Geological Formation and Sources
Understanding the geological origins of these gemstones provides insight into their rarity and unique characteristics. Each of the December birthstones forms under distinctly different conditions and is sourced from specific regions of the world.
Turquoise is a secondary mineral, meaning it forms in the arid regions of the world where water percolates through rocks containing copper, aluminum, and phosphorus. The sources do not specify exact mining locations for Turquoise, but its formation is typically associated with volcanic and sedimentary rocks. The most famous sources historically have been in Iran (Persia) and the Southwestern United States (Arizona, New Mexico, Nevada). The color of turquoise is directly influenced by its copper content, with higher copper levels yielding a more intense blue. The presence of iron and other impurities can shift the color toward green. The stone often contains a matrix of host rock, which can create unique spiderweb or veined patterns, adding to its character and value.
Zircon is a zirconium silicate mineral that forms in igneous and metamorphic rocks. It is a common accessory mineral found in many granite and syenite formations. The sources do not detail specific mining locations for Zircon, but it is mined in various locations worldwide, including Australia, Cambodia, Myanmar, and Sri Lanka. The blue variety of zircon, which is the most popular for jewelry, is typically produced by heating brown or yellow zircon crystals to high temperatures. This heat treatment removes the color-causing impurities and creates the desired blue hue. Natural blue zircon is rare, and the heat-treated variety is the standard in the gem market. Zircon crystals can be found in a range of sizes, and larger, well-formed crystals are highly valued by collectors.
Tanzanite has a very specific and limited geological origin. The sources explicitly state it was discovered in Tanzania in 1967. Further geological knowledge confirms that the only known commercial source of tanzanite is a small, four-square-kilometer mining area in the Merelani Hills of Northern Tanzania, near the base of Mount Kilimanjaro. This extreme rarity of location is a primary factor in its value. Tanzanite forms from the metamorphism of the mineral zoisite under specific heat and pressure conditions, which occurred during the formation of the East African Rift. The stones are typically mined from alluvial deposits, where they have been transported by water from their original host rock. The mining process is labor-intensive, contributing to the stone's scarcity in the global market.
Gemological Properties
The physical and optical properties of a gemstone determine its durability, appearance, and suitability for jewelry. Each of the December birthstones has a distinct set of characteristics.
Turquoise is a hydrated phosphate of copper and aluminum. Its hardness on the Mohs scale is relatively low, typically between 5 and 6. This makes it somewhat susceptible to scratching and damage, requiring careful handling. Turquoise is rarely transparent; it is almost always opaque. Its color ranges from sky blue to apple green, depending on the copper and iron content. The stone often contains a matrix or vein of the host rock, which is considered part of its natural beauty. Turquoise is porous and can be sensitive to chemicals, lotions, and even the oils from skin, which can cause discoloration over time. Many commercial turquoise stones are stabilized or treated with resins to enhance their durability and color stability.
Zircon is a zirconium silicate with a hardness of 7 to 7.5 on the Mohs scale, making it relatively durable and suitable for most types of jewelry, including rings. However, it can be brittle due to its crystal structure. Zircon exhibits a very high refractive index (1.92-2.01) and strong dispersion (0.039), which gives it exceptional brilliance and fire, often exceeding that of diamond. It is pleochroic, meaning it can show different colors when viewed from different crystal directions. Natural zircon comes in a variety of colors, including colorless, yellow, green, brown, and red. The blue variety, popular for December, is almost always the result of heat treatment of brown zircon. Zircon is also known for being radioactive in some specimens, particularly the brown varieties from certain locations, which can cause the crystal to become metamict (amorphous) over time.
Tanzanite is a variety of the mineral zoisite, with a chemical composition of Ca2Al3(SiO4)3(OH). It has a hardness of 6.5 to 7 on the Mohs scale, making it moderately durable but suitable for jewelry with care. Its most remarkable property is its trichroism: it can appear blue, violet, and burgundy depending on the crystal orientation. Most tanzanite on the market is heat-treated to a uniform blue-violet color, as the natural brownish-green rough is less desirable. The heat treatment is stable and is accepted as a standard industry practice. Tanzanite has a refractive index of 1.69-1.70 and is typically transparent to translucent. Its clarity is often very good, with fewer inclusions than many other gemstones.
Symbolism and Metaphysical Beliefs
Beyond their physical beauty, gemstones have long been imbued with symbolic meaning and metaphysical properties. The December birthstones are no exception, each carrying a legacy of beliefs.
Turquoise is universally regarded as a stone of protection, wisdom, and good fortune. The sources state it is "believed to bring good fortune and protection." In many cultures, it is considered a sacred stone. Native American tribes, such as the Navajo and Zuni, have used turquoise in jewelry and ceremonies for centuries, believing it connects the wearer to the sky and water. It is also associated with healing, emotional balance, and the chakra system, particularly the throat chakra for communication. The stone's calming color is thought to promote serenity and peace.
Zircon is associated with wisdom, honor, and purity. Historically, it was believed to aid in sleep and bring prosperity. Blue zircon, in particular, is linked to clarity of thought and spiritual growth. It is sometimes called the "stone of virtue" and is thought to promote honest and virtuous living. Some beliefs hold that zircon can help the wearer overcome obstacles and achieve their goals. Its brilliance is seen as a reflection of inner light and clarity.
Tanzanite, as a relatively new discovery, has quickly developed its own set of metaphysical beliefs. It is often associated with transformation, intuition, and spiritual awakening. Given its origin near the majestic Mount Kilimanjaro, it is seen as a stone of high vibration and spiritual connection. It is believed to open the mind to new perspectives and enhance psychic abilities. Its striking color is linked to the crown and third eye chakras, promoting insight and higher consciousness. Some also associate it with compassion and understanding.
Care and Cleaning
Proper care is essential to maintain the beauty and longevity of any gemstone. The different properties of Turquoise, Zircon, and Tanzanite require specific maintenance approaches.
Turquoise, with its relatively low hardness and porosity, demands the most care. It should be cleaned with a soft, dry cloth. Avoid using ultrasonic cleaners, steam cleaners, or any chemical solutions, as these can damage the stone or its stabilization treatment. Store turquoise jewelry separately to prevent scratching by harder gems. It is best to put on turquoise jewelry after applying lotions and perfumes and to remove it before swimming or engaging in activities that could expose it to harsh chemicals or impacts.
Zircon, while harder, can be brittle. It is generally safe to clean with warm soapy water and a soft brush. Avoid sudden temperature changes, as they can cause zircon to crack. Ultrasonic cleaners are usually safe for untreated zircon, but caution is advised for stones that have been fracture-filled or dyed. Due to its brittleness, zircon jewelry should be stored carefully to avoid impacts that could chip the stone.
Tanzanite requires gentle handling due to its hardness and potential for cleavage. Clean it with warm, soapy water and a soft brush. Avoid ultrasonic cleaners and steam cleaners, as the vibrations and heat can cause damage. It is also recommended to store tanzanite separately to prevent scratching. Given its value and rarity, having tanzanite jewelry professionally inspected and cleaned periodically is a good practice.
Conclusion
The birthstones of December—Turquoise, Zircon, and Tanzanite—offer a remarkable trio of gems, each with a unique story and set of characteristics. Turquoise provides ancient protection and a soothing sky-blue hue. Zircon offers brilliant fire and a connection to the Earth's deep history. Tanzanite contributes a modern rarity and captivating trichroic color. Together, they represent the diverse beauty of the winter month, providing a wealth of choices for those born in December. Their selection as birthstones is a testament to their enduring appeal, combining geological wonder with cultural significance and timeless beauty.
Sources
- https://funworldfacts.com/facts-about-december/
- https://www.almanac.com/content/month-of-december-holidays-facts-folklore
- https://www.thefactsite.com/december-facts/
- https://www.timeanddate.com/calendar/months/december.html