December, the final month of the year, is associated with not one, but four captivating gemstones. These stones—Blue Topaz, Blue Zircon, Tanzanite, and Turquoise—each offer a unique blend of color, history, and symbolism that makes them highly valued in the world of gemology. From the deep, inky blues of Blue Topaz to the mystical allure of Turquoise, December's birthstones reflect a rich tapestry of geological formation, cultural significance, and aesthetic appeal. This article will explore the properties, history, and significance of each of these four gemstones, offering a comprehensive guide for gemstone enthusiasts, jewelry buyers, and students of gemology alike.
A Historical Perspective on December’s Birthstones
The tradition of associating gemstones with the months of the year dates back centuries, with roots in ancient cultures that believed in the symbolic and protective powers of certain stones. For December, the selection of four birthstones reflects a balance between tradition and modernity, offering a range of options that vary in rarity, color, and affordability.
Blue Topaz, while not a traditional birthstone for December until the 20th century, has become a popular choice due to its striking blue color and relative affordability. Blue Zircon and Tanzanite, both relatively modern additions to the December birthstone list, add a range of vibrant hues and unique geological properties to the mix. Turquoise, the oldest of the four, has been cherished for millennia and holds deep cultural significance in many parts of the world.
Blue Topaz: A Modern Favorite
Blue Topaz is a silicate mineral composed of aluminum and fluorine. Its chemical formula is Al2SiO4(F,OH)4, and it typically exhibits a glass-like luster. Although topaz is naturally colorless, the blue varieties found in the December birthstone list are the result of irradiation treatment on naturally occurring colorless topaz. This treatment enhances the gem's color and makes it highly desirable in the jewelry market.
Blue Topaz is known for its versatility in jewelry design. It can be found in a range of shades, from the deep, inky blues of London Blue to the lighter, more vibrant tones of Swiss Blue and Sky Blue. The stone's durability, with a hardness of 8 on the Mohs scale, makes it suitable for everyday wear, although its strong cleavage can make it susceptible to damage if struck at the right angle.
The popularity of Blue Topaz as a birthstone has grown significantly since the 1960s, when it was officially designated as a December birthstone by the American National Association of Jewelers. Its affordability and wide availability have made it a favorite among jewelers and designers, who often use it in a variety of settings, from rings to pendants.
Blue Zircon: A Hidden Gem
Blue Zircon is another December birthstone that has gained popularity in recent decades. Zircon, a mineral that can occur in a wide range of colors, is often heat-treated to produce the vibrant blue hues found in this birthstone. The treatment enhances the gem's color and makes it more stable under light exposure. Blue Zircon typically has a hardness of 6 to 7.5 on the Mohs scale, making it suitable for jewelry, although it is more delicate than Blue Topaz.
One of the most intriguing aspects of Zircon is its long history in the gem world. Zircon has been known to exist for over 4 billion years, with some specimens found in ancient rocks being among the oldest materials on Earth. This makes Zircon not only a beautiful gemstone but also a piece of geological history. Blue Zircon is often compared to other blue gemstones like sapphire and aquamarine, but it has a distinct refractive index and a slightly more glassy appearance.
Tanzanite: A Unique Blue-Violet
Tanzanite is a relatively modern addition to the December birthstone list, having been discovered in Tanzania in the 1960s. Its deep blue-violet color is the result of a combination of trace elements and heat treatment. Tanzanite has a hardness of 6 to 7 on the Mohs scale, making it a suitable choice for jewelry, although it is more prone to chipping than some other gemstones.
One of the most fascinating aspects of Tanzanite is its geographical exclusivity. It is found only in Tanzania, making it one of the rarest gemstones in the world. This rarity has contributed to its value and made it a highly sought-after stone in the jewelry market. Tanzanite is also known for its pleochroism, a property that allows it to display different colors when viewed from different angles. This effect adds to its visual appeal and makes each piece of Tanzanite jewelry unique.
Turquoise: A Timeless Treasure
Turquoise is the oldest of the four December birthstones and has been cherished for thousands of years. This semi-translucent to opaque gemstone ranges in color from blue to green and often features veins of matrix—remnants of the rock in which it formed. Turquoise is a copper aluminum phosphate and forms in arid regions where rainwater or melted snow percolates through copper ore deposits. The acidic solution created by this process reacts with aluminum and potassium in the rocks, precipitating turquoise into cavities.
Turquoise has a relatively low hardness, ranging from 5 to 6 on the Mohs scale, which makes it more susceptible to damage than some other gemstones. It is also porous and can easily absorb oils, pigments, and moisture, which can alter its color. This makes proper care essential for preserving the beauty of Turquoise jewelry. The stone is often stabilized with resins or oils to enhance its durability and prevent discoloration.
Turquoise has been used in jewelry and ornaments for millennia. It was highly valued in ancient Egypt, where it was used to adorn pharaohs and other rulers. Chinese artisans carved Turquoise into intricate pieces over 3,000 years ago, and it was also an important gemstone in Native American cultures. The Apache believed that Turquoise could be found by following a rainbow to its end, while the Pueblo thought it got its color from the sky.
Symbolism and Metaphysical Beliefs
Each of December’s birthstones carries its own set of symbolic meanings and metaphysical beliefs. These associations have evolved over time, influenced by cultural traditions and individual interpretations.
Blue Topaz is often associated with calmness, serenity, and mental clarity. It is believed to help reduce stress and promote emotional balance. In ancient times, Topaz was thought to have protective properties and was used as a talisman to ward off illness and negative energy.
Blue Zircon is associated with wisdom, intuition, and spiritual growth. It is believed to enhance the ability to see the future and to help individuals connect with their inner selves. Zircon has also been used in ancient cultures as a protective stone, with some believing it could ward off evil spirits and bring good fortune.
Tanzanite is often linked to transformation, healing, and emotional release. It is believed to help individuals let go of the past and embrace new beginnings. Tanzanite is also associated with the heart chakra and is thought to promote love and compassion.
Turquoise has a rich history of symbolism and metaphysical beliefs. It has long been associated with protection, health, and good fortune. In ancient Egypt, Turquoise was believed to protect the wearer from evil and to bring prosperity. In Native American traditions, Turquoise is considered a sacred stone and is often used in rituals and ceremonies.
Geological Formation and Sources
The geological formation and sources of December’s birthstones vary significantly, reflecting the diverse conditions under which each gemstone is formed.
Blue Topaz is typically found in igneous rocks, particularly in pegmatites and rhyolites. These rocks form under high-temperature conditions, allowing the minerals within them to crystallize. Blue Topaz is found in several countries, including Brazil, the United States, and Nigeria. The treatment process that gives Blue Topaz its blue color is usually carried out in laboratories, where colorless Topaz is irradiated and then heated to enhance the color.
Blue Zircon is found in a variety of geological environments, including metamorphic and igneous rocks. It is often associated with granite and basalt formations. Zircon is found in countries such as Sri Lanka, Myanmar, and Cambodia, where it is mined and then heat-treated to produce the blue varieties associated with December’s birthstone list.
Tanzanite is found only in Tanzania, where it is mined in the Merelani Hills near the city of Arusha. The geological conditions in this region are unique, with the presence of trace elements such as vanadium and chromium contributing to the gem’s distinctive blue-violet color. The rarity of Tanzanite is due to the specific conditions required for its formation, which are not found anywhere else in the world.
Turquoise is formed in arid environments where copper-rich water reacts with aluminum and potassium in the surrounding rock. This process creates the characteristic blue and green hues of the gemstone. Turquoise is found in several countries, including Iran, the United States, and China. In the United States, important sources of Turquoise include the states of New Mexico, Arizona, and Nevada. The Kingman mine in Arizona is particularly well-known for producing high-quality Turquoise, while the now-closed Sleeping Beauty mine was once a prolific producer of the gemstone.
Care and Maintenance
Proper care and maintenance are essential for preserving the beauty and longevity of December’s birthstones. Each gemstone has specific care requirements based on its hardness, porosity, and chemical stability.
Blue Topaz is relatively durable and can be cleaned using a soft brush and mild soap in warm water. It is suitable for ultrasonic and steam cleaners, although care should be taken to avoid exposing the gemstone to sudden temperature changes or harsh chemicals. Blue Topaz should also be stored separately from other gemstones to prevent scratches, especially since it has a strong cleavage that can make it prone to chipping.
Blue Zircon requires more delicate care due to its lower hardness. It should be cleaned using a soft brush and mild soap in warm water, and ultrasonic and steam cleaners are generally not recommended. Blue Zircon can be sensitive to heat, and prolonged exposure to bright light may cause some heat-treated stones to revert to their original colors. It is best to avoid wearing Blue Zircon in rough conditions, such as during sports or household chores, to prevent damage.
Tanzanite is a relatively soft gemstone and requires careful handling. It should be cleaned using a soft brush and mild soap in warm water, and ultrasonic and steam cleaners should be used with caution. Tanzanite is sensitive to heat and can be damaged by prolonged exposure to direct sunlight. It is best to store Tanzanite in a cool, dry place and to avoid wearing it in situations where it may be subjected to impact or abrasion.
Turquoise is one of the more delicate December birthstones and requires special care. It is porous and can easily absorb oils, pigments, and moisture, which can alter its color. Turquoise should be cleaned using a soft brush and mild soap in warm water, and ultrasonic and steam cleaners should be avoided. It is best to store Turquoise in a sealed container to prevent it from drying out and losing its color. Turquoise should also be kept away from harsh chemicals, such as perfumes and lotions, which can cause discoloration.
Conclusion
December’s birthstones—Blue Topaz, Blue Zircon, Tanzanite, and Turquoise—each offer a unique combination of beauty, history, and symbolism. From the deep, inky blues of Blue Topaz to the mystical allure of Turquoise, these gemstones reflect a rich tapestry of geological formation, cultural significance, and aesthetic appeal. Whether you are drawn to the durability of Blue Topaz, the hidden beauty of Blue Zircon, the rarity of Tanzanite, or the timeless charm of Turquoise, there is a December birthstone to suit every taste and style. Understanding the properties, history, and care requirements of these gemstones allows for a deeper appreciation of their beauty and ensures their continued enjoyment for generations to come.