December is a month rich with tradition and symbolism, not least because it is associated with three distinct birthstones: blue topaz, blue zircon, and tanzanite. These gemstones, each with their own unique characteristics, have captivated jewelers, collectors, and gemstone enthusiasts for centuries. From their geological origins and chemical properties to their cultural significance and metaphysical associations, these stones offer a fascinating window into the world of gemology and beyond.
This article delves into the properties, history, and cultural lore of each of these December birthstones. Drawing on detailed information from authoritative sources, we will explore their formation, mining locations, gemological characteristics, and the meanings they have carried across time. Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, this comprehensive overview will provide you with a deeper understanding of these beautiful stones.
History and Lore
The tradition of birthstones dates back thousands of years, with early records indicating that gemstones were used for their symbolic and protective qualities. The concept of assigning specific gemstones to each month of the year is believed to have originated in ancient times, with the earliest known reference found in the Breastplate of Aaron, described in the Old Testament. This artifact was adorned with twelve gemstones, each representing one of the twelve tribes of Israel. Over time, these stones were linked to the months of the year, forming the foundation for the modern birthstone calendar.
For December, the selection of blue topaz, blue zircon, and tanzanite reflects the rich diversity of gemstones that have been cherished throughout history. Each of these stones carries its own unique narrative, from the ancient beliefs of medieval Europe to the scientific advancements of the modern era.
Blue Topaz
Blue topaz was once considered a rare and precious gemstone, but today it is widely available due to modern enhancement techniques. Historically, topaz has been associated with strength and protection. In ancient Egypt, it was believed to bring wisdom and courage to its wearer, while in medieval Europe, it was thought to promote love and friendship. The blue variety, however, did not exist in nature until the 20th century. Most blue topaz is created through a process of irradiation and heat treatment, which transforms colorless topaz into the vibrant blue gemstone we see today.
Blue Zircon
Zircon has a long and storied history, with references dating back to the Middle Ages. During this time, zircon was believed to aid sleep, bring prosperity, and promote honor and wisdom. The name "zircon" is derived from the Persian word zargun, meaning "gold-colored," a nod to the warm tones of some zircon varieties. The blue variety, in particular, is highly sought after for its brilliance and fire. Unlike many other gemstones, blue zircon is not enhanced through irradiation; rather, its color is a natural result of trace elements and heat treatment.
Tanzanite
Tanzanite is the most recent addition to the December birthstone list, discovered in the 1960s in Tanzania. Named after its country of origin, tanzanite is a rare and valuable gemstone that was once mistaken for another mineral. Its deep blue and purplish hues are a result of natural irradiation and heat treatment, a process that enhances its already striking color. Tanzanite quickly gained popularity due to its beauty and exclusivity, and it is now considered one of the most desirable gemstones of the modern era.
Geological Formation and Sources
Understanding the geological origins of a gemstone provides insight into its rarity, durability, and value. Each December birthstone is formed under unique conditions, and their sources are spread across the globe.
Blue Topaz
Topaz is a silicate mineral that forms in igneous rocks, particularly in pegmatites and rhyolites. In its natural state, topaz is colorless, but trace elements can impart color. The blue color in topaz is achieved through a process of irradiation and heat treatment. After the raw topaz is extracted from the earth and cut, it is irradiated to brown and then heated to sky blue. This enhancement is permanent and does not diminish the stone's value or beauty.
The primary sources of topaz are Brazil, Sri Lanka, and Australia. Brazil, in particular, is known for producing some of the finest topaz in the world. The availability of topaz has increased significantly over the years, making it more accessible to jewelers and consumers alike.
Blue Zircon
Zircon is a zirconium silicate mineral that forms in a variety of geological environments, including igneous, sedimentary, and metamorphic rocks. It is one of the oldest minerals on Earth, with some zircon crystals dating back over 4 billion years. Blue zircon is the most popular color variation, and its formation is influenced by natural radiation and heat. Unlike blue topaz, blue zircon is not enhanced through artificial means; its color is a natural result of the mineral's composition and the environment in which it forms.
Major sources of zircon include Thailand, Cambodia, and Vietnam. These countries are known for producing high-quality zircon with excellent clarity and color. The availability of zircon has made it a popular choice for jewelry designers, who appreciate its brilliance and affordability.
Tanzanite
Tanzanite is a rare gemstone that is found exclusively in the Merelani Hills of Tanzania. It is a variety of the mineral zoisite, and its unique blue and purple hues are the result of natural irradiation and heat treatment. Tanzanite was first discovered in the 1960s, and it quickly gained popularity due to its beauty and scarcity. It is estimated that only a small amount of tanzanite is mined each year, making it one of the most exclusive gemstones in the world.
The rarity of tanzanite is further compounded by the fact that it is only found in one location on Earth. This exclusivity has made tanzanite highly desirable among collectors and jewelers. Due to its limited supply, tanzanite is expected to become even more valuable in the future.
Gemological Properties
The physical and optical properties of a gemstone determine its appearance, durability, and suitability for jewelry. Each December birthstone has its own unique set of characteristics that contribute to its beauty and value.
Blue Topaz
Blue topaz is a durable gemstone that ranks 8 on the Mohs Scale of Hardness. This high rating means that it is resistant to scratches and can be worn daily without significant damage. Its chemical formula is Al₂SiO₄(F,OH)₂, and it has a refractive index of 1.61–1.63. Blue topaz is typically transparent to translucent and is known for its brilliance and fire.
One of the most distinctive features of blue topaz is its clarity. It is often free of inclusions, making it an excellent choice for jewelry. Its color is enhanced through a process of irradiation and heat treatment, which is permanent and does not affect the stone's durability.
Blue Zircon
Blue zircon is a zirconium silicate mineral that ranks 7.5 on the Mohs Scale of Hardness. While it is not as hard as blue topaz, it is still a durable gemstone that can be worn in everyday jewelry. Its chemical formula is ZrSiO₄, and it has a refractive index of 1.90–2.00, which is higher than that of blue topaz. This high refractive index gives blue zircon a brilliant and fiery appearance.
Blue zircon is known for its excellent clarity, and it is often free of inclusions. However, it is important to note that blue zircon is sensitive to rough wear and can be easily abraded. Therefore, it is best suited for jewelry that is worn occasionally rather than daily.
Tanzanite
Tanzanite is a zoisite mineral that ranks 6.5–7 on the Mohs Scale of Hardness. While it is not as hard as blue topaz or blue zircon, it is still a durable gemstone that can be worn in jewelry. Its chemical formula is Ca₂Al₃(SiO₄)(Si₂O₇)O(OH), and it has a refractive index of 1.694–1.702. Tanzanite is known for its deep blue and purplish hues, which are the result of natural irradiation and heat treatment.
Tanzanite is typically translucent to transparent and is known for its excellent clarity. However, it is important to note that tanzanite is sensitive to heat and chemicals, and it should be handled with care to avoid damage. Due to its rarity and beauty, tanzanite is considered a high-value gemstone and is often used in fine jewelry.
Symbolism and Metaphysical Beliefs
Throughout history, gemstones have been associated with a wide range of symbolic and metaphysical properties. These beliefs vary across cultures and time periods, but they have played an important role in the popularity and use of gemstones.
Blue Topaz
Blue topaz has long been associated with strength, protection, and emotional balance. In ancient Egypt, it was believed to bring wisdom and courage to its wearer. In medieval Europe, it was thought to promote love and friendship. In modern times, blue topaz is believed to enhance calmness and clarity, making it a popular choice for those seeking emotional balance.
In metaphysical circles, blue topaz is associated with the throat chakra and is believed to enhance communication and self-expression. It is also believed to promote a sense of calm and reduce stress, making it an ideal stone for those who are seeking inner peace.
Blue Zircon
Blue zircon has been associated with prosperity, honor, and wisdom in medieval Europe. It was believed to aid sleep and promote a sense of well-being. In modern times, blue zircon is believed to enhance intuition and psychic abilities. It is also associated with the heart chakra and is believed to promote love and compassion.
Blue zircon is considered a powerful stone for those who are seeking emotional healing and spiritual growth. It is also believed to enhance creativity and inspire new ideas, making it a popular choice for artists and dreamers.
Tanzanite
Tanzanite is a relatively new gemstone, but it has quickly gained a reputation for its powerful metaphysical properties. It is associated with the heart and throat chakras and is believed to promote emotional healing and self-expression. Tanzanite is also believed to enhance intuition and spiritual awareness, making it a popular choice for those who are seeking deeper spiritual connections.
In addition to its emotional and spiritual properties, tanzanite is also believed to promote inner strength and resilience. It is a symbol of transformation and change, making it an ideal stone for those who are going through a period of transition.
Care and Cleaning
Proper care and cleaning are essential for maintaining the beauty and longevity of gemstones. Each December birthstone has its own specific care requirements, based on its physical and chemical properties.
Blue Topaz
Blue topaz is a durable gemstone that can be cleaned with warm, soapy water and a soft cloth. It is resistant to scratches and can be worn daily without significant damage. However, it is important to avoid prolonged exposure to direct sunlight or extreme heat, as this can cause fading.
Blue topaz should be stored separately from other gemstones to prevent scratches. It is also important to avoid using harsh chemicals or ultrasonic cleaners, as these can damage the stone.
Blue Zircon
Blue zircon is a durable gemstone, but it is sensitive to rough wear and abrasion. It can be cleaned with warm, soapy water and a soft cloth. However, it is important to avoid using ultrasonic cleaners or steam cleaners, as these can damage the stone.
Blue zircon should be stored separately from other gemstones to prevent scratches. It is also important to avoid exposure to harsh chemicals, as these can damage the stone's surface.
Tanzanite
Tanzanite is a relatively soft gemstone that requires careful handling. It can be cleaned with warm, soapy water and a soft cloth, but it is important to avoid using ultrasonic cleaners or steam cleaners, as these can damage the stone.
Tanzanite should be stored separately from other gemstones to prevent scratches. It is also important to avoid exposure to heat and chemicals, as these can damage the stone's surface.
Conclusion
The December birthstones—blue topaz, blue zircon, and tanzanite—each offer a unique combination of beauty, history, and symbolism. From their geological origins and gemological properties to their cultural significance and metaphysical associations, these stones continue to captivate gemstone enthusiasts and jewelry lovers alike. Whether worn for their beauty, their meaning, or their rarity, these December birthstones are a testament to the enduring appeal of gemstones throughout history.
Understanding the properties and care requirements of these stones ensures that they can be enjoyed for generations to come. As you explore the world of December birthstones, you will discover not only the physical characteristics that make these gemstones so special, but also the rich traditions and beliefs that have shaped their place in human history.