December, the final month of the year, is symbolically rich and gemologically diverse. For those born in this month, the birthstone selection is not just a single gemstone but a collection of four distinct options: turquoise, tanzanite, blue zircon, and blue topaz. Each of these gemstones carries its own unique set of characteristics, historical significance, and cultural symbolism. From the ancient allure of turquoise to the modern discovery of tanzanite, December's birthstones represent a fascinating blend of tradition and innovation in the world of gemology.
This article provides a comprehensive overview of each of these four December birthstones, exploring their geological origins, physical properties, historical and cultural uses, and their roles in contemporary jewelry. Whether you are a gemstone enthusiast, a jewelry buyer, or simply curious about the stones associated with this month, this guide will offer valuable insights into the beauty and significance of December’s birthstones.
History and Lore
The tradition of assigning gemstones to specific months dates back centuries, with the earliest known records appearing in ancient texts from India, China, and Europe. Over time, these associations evolved, often influenced by cultural beliefs, availability of the stones, and shifts in fashion. December’s birthstone list is particularly unique because it includes not one, but four gemstones, each with its own historical background.
Turquoise: The Ancient Gem
Turquoise is among the oldest known gemstones, with a history that spans thousands of years. As early as 3000 BCE, turquoise was mined in Egypt and used to craft jewelry, amulets, and inlay work. It was so highly prized that it was often referred to as the "stone of life." The ancient Egyptians believed turquoise brought protection and good fortune, and it was often used in burial amulets.
In the Americas, turquoise held significant cultural and spiritual importance for Native American tribes, particularly among the Navajo, Pueblo, and Zuni. These cultures used turquoise in jewelry, ceremonial objects, and as a medium for trade. The stone was considered a symbol of health, prosperity, and connection to the divine.
In Europe, turquoise was often incorporated into rings and pendants, symbolizing love and affection. The stone's popularity waned during the Renaissance but was revived in the 19th and 20th centuries as part of the Art Deco movement and later as a key component of Native American-inspired jewelry.
Tanzanite: A Modern Discovery
Tanzanite is the newest addition to the December birthstone list, having been officially recognized in 2002. It was discovered in the late 1960s in Tanzania, near the foothills of Mount Kilimanjaro. The first specimen was found by a Maasai tribesman named Jumanne Ngoma, who stumbled upon the stone while herding goats. The gem was initially misidentified as a sapphire, but further analysis by the Gemological Institute of America (GIA) revealed it to be a new and unique variety of the mineral zoisite.
The marketing of tanzanite was a strategic effort led by Tiffany & Co., which sought to create a name that would resonate with the public. The original name "blue zoisite" was deemed too unappealing, so the company opted for "tanzanite," a name that honored the country of origin and helped to establish the stone's identity.
Tanzanite quickly gained popularity due to its striking color and rarity. It was also designated as the gemstone for the 24th wedding anniversary, further enhancing its cultural significance. The stone’s vibrant blue-violet hues and pleochroic nature (its ability to display different colors when viewed from different angles) make it a favorite among jewelers and collectors alike.
Blue Zircon and Blue Topaz: Ancient and Modern Alternatives
Blue zircon and blue topaz are the other two traditional December birthstones. Blue zircon, also known as hyacinth in historical contexts, has been used in jewelry for centuries. It was highly valued in the Middle Ages and Renaissance periods for its brilliance and clarity. However, due to its relative obscurity and the challenges in distinguishing it from other blue gemstones like sapphires, blue zircon did not achieve the same level of widespread recognition as turquoise or tanzanite.
Blue topaz, on the other hand, has a more recent history in the birthstone tradition. It was added to the December list as a modern alternative, providing a more affordable and durable option for jewelry. Blue topaz is known for its bright blue color and its association with love and affection in ancient Hindu traditions. Its popularity has grown in recent decades, making it a popular choice for rings, necklaces, and other fine jewelry pieces.
Geological Formation and Sources
Understanding the geological processes that form each of December’s birthstones provides insight into their rarity, color, and availability. Each gemstone has a unique formation history and set of sources, which contribute to its desirability in the jewelry market.
Turquoise: A Product of Weathering and Mineralization
Turquoise is formed through a process of weathering and mineralization. It typically occurs in arid regions where copper-rich rocks are exposed to the elements. Rainwater or melted snow percolates through these copper deposits, creating an acidic solution that reacts with aluminum and potassium in the surrounding rocks. This reaction leads to the formation of turquoise in cavities within the rock.
The most well-known sources of turquoise include Iran, the United States (particularly Arizona and Nevada), and China. Each of these regions produces turquoise with distinct color variations. Iranian turquoise, often referred to as "Persian blue," is highly prized for its deep blue color and minimal matrix. American turquoise, especially from the Southwest, is known for its vibrant colors and intricate matrix patterns.
Tanzanite: A Unique Geological Phenomenon
Tanzanite is one of the rarest gemstones in the world due to its exclusive source in Tanzania. The gemstone forms under specific geological conditions where the mineral zoisite is subjected to heat and pressure, causing a transformation that results in the blue-violet coloration. This transformation is believed to be the result of the presence of trace elements such as vanadium and iron.
The deposits of tanzanite are located in the Merelani Hills of Tanzania, a region known for its unique geological formations. Because the source is limited and the gemstone is only found in this area, tanzanite is considered a finite resource. Its rarity, combined with its striking color and brilliance, contributes to its high value in the gemstone market.
Blue Zircon and Blue Topaz: Diverse Origins and Formation
Blue zircon is a naturally occurring zircon that has been heat-treated to enhance its blue color. Zircon is found in various parts of the world, including Thailand, Cambodia, and Australia. The blue coloration is achieved through a controlled heating process that alters the gemstone’s crystal structure, resulting in a vibrant blue hue. Blue zircon is known for its high refractive index, which gives it a brilliant sparkle and makes it a popular choice for jewelry.
Blue topaz, on the other hand, is a naturally occurring topaz that has been treated with irradiation and heat to achieve its blue color. Topaz is found in several countries, including Brazil, the United States, and Nigeria. The blue topaz used in jewelry is typically sourced from these regions and then treated to enhance its color. Blue topaz is known for its durability and affordability, making it an accessible option for everyday jewelry.
Gemological Properties
Each of December’s birthstones has distinct gemological properties that contribute to their beauty and desirability in jewelry. These properties include hardness, refractive index, color, and other characteristics that influence how the gemstone is used and cared for.
Turquoise: Soft and Porous
Turquoise has a relatively low hardness on the Mohs scale, ranging from 5 to 6. This makes it more susceptible to scratches and damage compared to other gemstones. Additionally, turquoise is a porous and opaque stone, which means it can be easily stained by oils, pigments, and other substances. Because of these properties, turquoise is best suited for jewelry that is not worn daily, such as earrings or pendants.
The color of turquoise can vary from a deep blue to a greenish-blue, depending on the concentration of copper and the presence of other minerals. The most valuable turquoise has a consistent, deep blue color with minimal matrix (the dark veins or patterns that run through the stone).
Tanzanite: Color-Changing and Pleochroic
Tanzanite has a hardness of 6 to 6.5 on the Mohs scale, which means it is relatively durable but still requires care to avoid scratches and chips. One of the most remarkable properties of tanzanite is its pleochroism—the ability to display different colors when viewed from different angles. Tanzanite can appear blue, violet, or even red depending on the angle of light and the viewer’s perspective.
The refractive index of tanzanite is high, which contributes to its brilliance and fire. Tanzanite is also known for its excellent clarity, with many stones exhibiting a glassy, transparent appearance. These properties make tanzanite a popular choice for rings, pendants, and other fine jewelry pieces.
Blue Zircon and Blue Topaz: Durable and Brilliant
Blue zircon has a hardness of 7.5 to 8 on the Mohs scale, making it more durable than turquoise but less hard than tanzanite. Blue zircon has a high refractive index and a strong dispersion, which gives it a brilliant sparkle and a fiery appearance. Blue zircon is often used in rings, earrings, and pendants due to its durability and brilliance.
Blue topaz has a hardness of 8 on the Mohs scale, making it one of the most durable of December’s birthstones. It has a high refractive index and a low dispersion, which means it is not as fiery as blue zircon but still has a brilliant, clear appearance. Blue topaz is often used in rings, necklaces, and bracelets due to its durability and affordability.
Symbolism and Metaphysical Beliefs
The symbolic meanings and metaphysical properties of December’s birthstones have been passed down through generations, influencing their use in jewelry and their popularity in different cultures.
Turquoise: Protection and Good Fortune
Turquoise has long been associated with protection, good fortune, and health. In ancient Egypt, it was believed to ward off evil spirits and bring prosperity to the wearer. In Native American cultures, turquoise is considered a sacred stone that connects the earth and sky. It is often used in healing rituals and is believed to promote emotional balance and spiritual harmony.
In modern times, turquoise is still associated with protection and good luck. It is often given as a gift to symbolize friendship and affection. The stone is also believed to enhance communication and self-expression, making it a popular choice for those who seek to improve their relationships and personal growth.
Tanzanite: Wisdom and Inner Strength
Tanzanite is believed to promote wisdom, inner strength, and emotional healing. Its deep blue-violet color is associated with calmness and serenity, making it a popular choice for those who seek balance and clarity in their lives. Tanzanite is also believed to enhance intuition and spiritual awareness, making it a favorite among those who practice meditation and mindfulness.
In some cultures, tanzanite is used as a tool for manifestation, helping the wearer to attract their desires and align with their true purpose. It is also believed to support the throat chakra, which is associated with communication and self-expression.
Blue Zircon and Blue Topaz: Love and Clarity
Blue zircon is believed to enhance clarity of thought and promote emotional stability. It is often used in meditation and is associated with the heart and throat chakras. Blue zircon is also believed to bring a sense of peace and calm to the wearer, making it a popular choice for those who seek to reduce stress and anxiety.
Blue topaz is associated with love, affection, and emotional healing. It is believed to promote inner strength and self-confidence, helping the wearer to overcome challenges and achieve their goals. Blue topaz is also believed to attract positive energy and enhance communication, making it a popular choice for those who seek to improve their relationships and personal growth.
Care and Cleaning
Proper care and cleaning are essential to preserving the beauty and longevity of December’s birthstones. Each gemstone has specific care requirements based on its hardness, porosity, and sensitivity to chemicals and heat.
Turquoise
Turquoise is a soft and porous gemstone that requires gentle care. It should be cleaned with a soft, damp cloth and a mild soap solution. Harsh chemicals, ultrasonic cleaners, and steam cleaners should be avoided, as they can damage the stone or cause discoloration. Turquoise should also be kept away from direct sunlight and extreme temperatures, as these can cause it to lose its color or become brittle.
Turquoise jewelry should be stored separately from other gemstones to prevent scratches and abrasions. It is also important to avoid exposing turquoise to oils, perfumes, and lotions, as these can stain or dull the stone.
Tanzanite
Tanzanite is relatively durable but should still be handled with care to avoid scratches and chips. It can be cleaned with a soft, damp cloth and a mild soap solution. Ultrasonic and steam cleaners can be used, but it is important to ensure that the gemstone is free of inclusions or fractures that could be worsened by the cleaning process.
Tanzanite should be stored in a soft pouch or jewelry box to prevent scratches from harder gemstones. It should also be kept away from direct sunlight and extreme temperatures, as these can affect the color and stability of the stone.
Blue Zircon and Blue Topaz
Blue zircon and blue topaz are more durable and can withstand a wider range of cleaning methods. Both gemstones can be cleaned with a soft, damp cloth and a mild soap solution. Ultrasonic and steam cleaners can also be used, but it is important to ensure that the gemstone is free of inclusions or fractures that could be worsened by the cleaning process.
Blue zircon and blue topaz should be stored separately from harder gemstones to prevent scratches. They can be exposed to sunlight and moderate heat without causing damage, but it is still advisable to avoid prolonged exposure to extreme temperatures.
Conclusion
December’s birthstones—turquoise, tanzanite, blue zircon, and blue topaz—each bring their own unique beauty, history, and significance to the world of gemology. From the ancient allure of turquoise to the modern discovery of tanzanite, these gemstones reflect the rich traditions and evolving trends in the jewelry industry. Whether you are drawn to the deep blue hues of tanzanite, the vibrant sparkle of blue zircon, or the classic elegance of turquoise and blue topaz, there is a December birthstone for every taste and occasion.
Understanding the geological properties, historical significance, and care requirements of these gemstones allows for a deeper appreciation of their beauty and value. Whether you are considering a December birthstone for yourself or as a gift for a loved one, these stones offer a timeless connection to nature, culture, and personal meaning.