December, the final month of the year, is uniquely distinguished in the world of gemology by its rich and varied array of birthstones. Unlike many months that are represented by a single gemstone, December boasts a collection of five gemstones, each with its own distinct beauty, historical significance, and symbolic meaning. These stones—blue zircon, blue topaz, tanzanite, lapis lazuli, and turquoise—offer a remarkable diversity that reflects the month’s wintry charm and its deep cultural roots. The December birthstone list is a testament to the evolving nature of gemological traditions and the enduring appeal of colored gemstones in human culture.
This article delves into the multifaceted world of December birthstones, exploring their geological formation, historical uses, symbolic meanings, and practical care tips. From the ancient allure of lapis lazuli to the modern discovery of tanzanite, each gemstone tells a story that spans centuries, continents, and civilizations. Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, this comprehensive guide will provide you with a deeper understanding of why December's birthstones remain so cherished.
A Historical Journey Through December Birthstones
The concept of birthstones is deeply rooted in historical and cultural traditions that have evolved over time. In ancient times, gemstones were believed to possess mystical powers and were often used as protective talismans. The earliest known references to birthstones can be traced back to the Bible, specifically the Breastplate of Aaron, described in the Book of Exodus. This sacred artifact contained twelve gemstones, each representing one of the twelve tribes of Israel. However, the specific stones and their associations have changed significantly over time, especially as new gem varieties were discovered and scientific understanding of minerals advanced.
December has a particularly interesting history when it comes to its birthstones. The earliest recorded gemstone associated with December was ruby, a red gemstone that symbolized strength and vitality. However, this association did not persist into modern times. Instead, the December birthstone list has evolved through the centuries, incorporating new gemstones as they became more widely known and accessible. For example, in 1870, turquoise was designated as the December birthstone by Tiffany & Co. in their "Gregorian Birthstone Poems" pamphlet. This marked the beginning of a more modern approach to birthstone symbolism.
By 1912, the National Association of Jewellers (now known as Jewellers of America) updated the list, listing turquoise as the primary December birthstone and lapis lazuli as an alternative. In 1952, zircon was added to the list, and in 2002, tanzanite joined the ranks of December birthstones. This gradual expansion reflects the dynamic nature of gemological traditions and the influence of both cultural and commercial factors in shaping the modern birthstone list.
The inclusion of multiple gemstones for December also serves a practical purpose. It provides a range of options that cater to different tastes, budgets, and personal preferences. For instance, turquoise and lapis lazuli are traditional choices that evoke a sense of history and tradition, while blue topaz, zircon, and tanzanite offer more modern alternatives with varying levels of rarity and value. This diversity ensures that individuals born in December have access to a wide array of gemstones that can be tailored to their individual style and needs.
Geological Formation and Sources of December Birthstones
The geological formation and geographical distribution of December birthstones are as diverse as the stones themselves. Each gemstone has its own unique origin story, shaped by the natural processes of the Earth and the conditions under which it forms.
Blue Zircon
Blue zircon is a metamorphic mineral that forms under high heat and pressure, often in the presence of radioactive elements. The blue color in zircon is a result of irradiation followed by heat treatment, a process that alters the crystal structure and creates a vibrant blue hue. Zircon is one of the oldest minerals on Earth, with some zircon crystals found in Western Australia dating back over 4 billion years. This makes zircon not only a beautiful gemstone but also a geological time capsule that offers insights into the early history of the planet.
Zircon is found in various parts of the world, including Australia, Sri Lanka, and Brazil. However, the blue variety that is commonly used in jewelry is typically sourced from Madagascar and Cambodia. The rarity of natural blue zircon makes it a highly sought-after gemstone, especially in the December birthstone category.
Blue Topaz
Blue topaz is a silicate mineral that forms in igneous rocks, particularly in cavities within granite and rhyolite. The blue color in topaz is caused by trace amounts of iron and irradiation. Natural blue topaz is relatively rare, so most of the blue topaz available in the market is produced through a process known as irradiation and heat treatment. This treatment enhances the natural color and makes it more consistent.
Brazil is the largest producer of topaz, particularly the blue variety. Other notable sources include the United States, Nigeria, and China. Blue topaz is valued for its clarity, brilliance, and affordability, making it a popular choice for those who appreciate the aesthetic of a blue gemstone without the high price tag of more rare options.
Tanzanite
Tanzanite is a relatively modern discovery in the world of gemstones. It was first discovered in 1967 in the Merelani Hills near Mount Kilimanjaro in Tanzania. This gemstone is a type of zoisite that undergoes heat treatment to enhance its color, which ranges from deep blue to violet. The unique color of tanzanite is due to the presence of vanadium, which is activated by heat and irradiation.
Tanzanite is exclusive to Tanzania, making it one of the few gemstones that can be found in only one country. This exclusivity contributes to its high value and makes it a symbol of rarity and uniqueness. The gemstone was named after its country of origin, and it has quickly become a favorite among jewelers and collectors alike.
Lapis Lazuli
Lapis lazuli is a metamorphic rock composed primarily of lazurite, a sodium calcium aluminum silicate. It is known for its deep blue color, which is caused by the presence of sulfur. Lapis lazuli also contains other minerals such as pyrite, which gives it a golden sparkle, and calcite, which appears as white streaks.
The most famous source of lapis lazuli is Afghanistan, where it has been mined for thousands of years. This gemstone has been used in ancient civilizations such as Egypt, Mesopotamia, and the Indus Valley. Lapis lazuli was highly prized in ancient times and was often used to make jewelry, amulets, and even pigments for paint. Its association with wisdom, truth, and royalty has made it a symbol of intellectual and spiritual enlightenment.
Turquoise
Turquoise is a hydrated phosphate of aluminum and copper, and it forms in the weathering zones of copper deposits. It is typically found in arid regions where the conditions are suitable for its formation. The blue-green color of turquoise is due to the presence of copper, while the presence of iron gives it a greenish tint.
The most well-known source of turquoise is the United States, particularly in the southwestern states such as Arizona, New Mexico, and Nevada. Other notable sources include Egypt, China, and Iran. Turquoise has a long history of use in jewelry and decorative arts, especially among Native American cultures, where it is considered a sacred stone with protective and healing properties.
Gemological Properties of December Birthstones
Understanding the gemological properties of December birthstones is essential for appreciating their beauty, durability, and suitability for jewelry. Each gemstone has its own unique set of characteristics that define its appearance and value.
Blue Zircon
Blue zircon has a hardness of 6.5 to 7.5 on the Mohs scale, making it a relatively durable gemstone. It has a refractive index of 1.92 to 2.00, which contributes to its brilliance and fire. Blue zircon is known for its high dispersion, which creates a rainbow of colors when light passes through it. This makes it a popular choice for those who want a gemstone with a fiery sparkle.
Blue Topaz
Blue topaz has a hardness of 8 on the Mohs scale, which makes it more durable than blue zircon. It has a refractive index of 1.61 to 1.63 and a dispersion of 0.008 to 0.014, which is lower than that of zircon. Blue topaz is prized for its clarity and its ability to transmit light, which gives it a bright and lively appearance.
Tanzanite
Tanzanite has a hardness of 6 to 7 on the Mohs scale, which means it is relatively soft and requires careful handling. It has a refractive index of 1.694 to 1.701 and a dispersion of 0.022, which gives it a moderate amount of fire. Tanzanite is known for its trichroism, a property that allows it to display different colors when viewed from different angles. This makes it a fascinating gemstone to study and admire.
Lapis Lazuli
Lapis lazuli is a metamorphic rock with a hardness of 5 to 6 on the Mohs scale. It is not a single mineral but a combination of lazurite, pyrite, and calcite. Its refractive index is relatively low, and it does not display high levels of dispersion. Lapis lazuli is valued for its deep blue color and its golden flecks of pyrite, which give it a unique and eye-catching appearance.
Turquoise
Turquoise has a hardness of 5 to 6 on the Mohs scale, which makes it a relatively soft gemstone that requires careful handling. It has a refractive index of 1.61 to 1.65 and a low dispersion. Turquoise is known for its vibrant blue-green color and its ability to absorb oils and waxes, which can affect its appearance over time. It is often treated with resins or waxes to enhance its color and stability.
Symbolism and Metaphysical Beliefs
The symbolic and metaphysical significance of December birthstones is as rich and varied as their geological and historical backgrounds. These gemstones have been associated with various meanings and powers across different cultures and time periods, adding to their enduring appeal.
Blue Zircon
Blue zircon is often associated with wisdom, clarity, and spiritual insight. In ancient times, it was believed to have protective properties and was used as a talisman for travelers. In modern gemology, blue zircon is considered a stone of transformation, helping individuals to overcome challenges and embrace change. It is also associated with the throat chakra, which is linked to communication and self-expression.
Blue Topaz
Blue topaz is believed to have a calming and soothing effect, making it a popular choice for those seeking emotional balance and inner peace. It is associated with the heart chakra and is thought to promote love, compassion, and understanding. Blue topaz is also believed to enhance intuition and provide protection against negative energies.
Tanzanite
Tanzanite is known as a stone of transformation and spiritual growth. It is believed to help individuals release emotional blockages and embrace new possibilities. It is associated with the heart and crown chakras, which are linked to love, spiritual connection, and higher consciousness. Tanzanite is also believed to enhance creativity and inspire new ideas.
Lapis Lazuli
Lapis lazuli has long been associated with wisdom, truth, and enlightenment. In ancient Egypt, it was used by royalty and priests, and it was believed to enhance intellectual abilities and promote a deeper understanding of the world. In modern times, lapis lazuli is considered a stone of inner truth and self-awareness. It is associated with the third eye and throat chakras, which are linked to intuition, communication, and spiritual insight.
Turquoise
Turquoise is one of the most well-known and revered gemstones in the world of metaphysical beliefs. It is often referred to as a stone of protection, healing, and good fortune. In many Native American cultures, turquoise is considered a sacred stone that provides protection and connects the wearer to the earth and the sky. It is also associated with the throat and heart chakras, which are linked to communication, love, and emotional balance.
Care and Cleaning of December Birthstones
Proper care and cleaning are essential for maintaining the beauty and longevity of December birthstones. Each gemstone has its own specific care requirements, which are based on its hardness, chemical composition, and sensitivity to heat and light.
Blue Zircon
Blue zircon is relatively durable but should still be handled with care. It can be cleaned with warm, soapy water and a soft cloth. Avoid using ultrasonic cleaners or steamers, as these can damage the gemstone. Blue zircon should be stored separately from harder gemstones to prevent scratches.
Blue Topaz
Blue topaz is a durable gemstone that can be cleaned with warm, soapy water and a soft cloth. It can also be cleaned with ultrasonic cleaners and steamers. Blue topaz should be stored in a dry place to prevent any damage from moisture.
Tanzanite
Tanzanite is a relatively soft gemstone that requires careful handling. It can be cleaned with warm, soapy water and a soft cloth. Avoid using ultrasonic cleaners or steamers, as these can cause damage. Tanzanite should be stored in a cool, dry place away from direct sunlight.
Lapis Lazuli
Lapis lazuli is a metamorphic rock that is relatively soft and requires gentle care. It can be cleaned with warm, soapy water and a soft cloth. Avoid using harsh chemicals or abrasive materials, as these can damage the surface of the stone. Lapis lazuli should be stored in a cool, dry place away from direct sunlight.
Turquoise
Turquoise is a relatively soft gemstone that requires special care. It can be cleaned with warm, soapy water and a soft cloth. Avoid using harsh chemicals or abrasive materials, as these can damage the surface of the stone. Turquoise should be stored in a cool, dry place away from direct sunlight. It is also important to avoid exposing turquoise to oils, perfumes, and lotions, as these can affect its appearance over time.
Conclusion
December birthstones—blue zircon, blue topaz, tanzanite, lapis lazuli, and turquoise—represent a unique and diverse collection of gemstones that reflect the richness of human history, culture, and nature. From their geological formation and geographical sources to their symbolic meanings and metaphysical properties, these gemstones offer a fascinating glimpse into the world of gemology. Whether you are drawn to the deep blue of lapis lazuli, the vibrant hues of turquoise, the brilliant fire of blue zircon, the calming energy of blue topaz, or the transformative power of tanzanite, there is a December birthstone that resonates with your personal style and values. With proper care and appreciation, these gemstones can continue to shine for generations to come, serving as enduring symbols of beauty, wisdom, and connection.