December is a month rich in symbolism, celebration, and, in the world of gemology, an impressive array of birthstones. Unlike months that are assigned a single birthstone, December is uniquely associated with four distinct gems: tanzanite, turquoise, zircon, and blue topaz. Each of these gemstones carries its own geological history, cultural significance, and aesthetic appeal. Together, they represent a spectrum of blue, from the deep, velvety tones of tanzanite to the bright, sky-blue brilliance of turquoise. This article explores the origins, properties, symbolism, and care of these December birthstones, drawing from historical records, scientific data, and modern gemological practices.
History and Lore
Tanzanite: A Modern Marvel
Tanzanite is a relatively recent addition to the world of gemstones, having been discovered in 1967 in the Merelani Hills of northern Tanzania. Before its discovery, the blue stones found in the region were classified as zoisite, a mineral that is typically brown or green. It was only after a thorough analysis and enhancement process that the unique blue-violet hues of tanzanite were revealed, marking its emergence as a distinct gemstone.
The name "tanzanite" was chosen to honor its country of origin, Tanzania. The gem quickly gained popularity, thanks in part to a major advertising campaign by Tiffany & Co. in 1968. This campaign highlighted tanzanite's vibrant color, high clarity, and potential for large cut stones, which made it a favorite among jewelers and collectors. Today, tanzanite is not only a December birthstone but also a symbol of the 24th wedding anniversary.
The Merelani Hills, where tanzanite is exclusively mined, are located near Mount Kilimanjaro. The region is characterized by grass-covered hillsides, rocky soil, and scrub brush. The mining process is labor-intensive, with thousands of workers operating in mines that extend over 100 meters into the earth. The scarcity of tanzanite, combined with its striking color, ensures that it remains a highly valued gemstone in the global market.
Turquoise: An Ancient Gem
Turquoise is one of the oldest known gemstones, with evidence of its use dating back to around 3000 BCE. It was highly prized by ancient civilizations such as the Egyptians, Persians, and Native Americans. In ancient Egypt, turquoise was associated with the goddess Hathor, who was often depicted with the gemstone. It was also used in amulets and jewelry to provide protection and bring good fortune.
The stone's name, "turquoise," is derived from the French word for Turkey, as it was once believed that the gemstone was brought to Europe via the country. In reality, the most famous turquoise deposits were in Persia, now Iran, where the deep blue "Persian blue" turquoise is still highly sought after.
In the Americas, turquoise played a significant role in Native American cultures, particularly among the Navajo and Zuni tribes. It was used in ceremonial objects and jewelry, symbolizing health, protection, and spiritual connection. Turquoise rings were also exchanged in European traditions as tokens of affection, while in Tibet, the gemstone is considered a national treasure.
The United States has also been an important source of turquoise, particularly in the early 20th century. Arizona and Nevada are currently the primary U.S. sources, with the Kingman mine in Arizona being a historically significant producer. The Sleeping Beauty mine in Arizona, once a prolific turquoise producer, has since been closed to turquoise mining.
China has emerged as the world's largest producer of turquoise, with most of the gem-quality turquoise coming from Hubei Province. The Chinese turquoise is known for its consistent blue color and high quality, making it a popular choice for jewelry and decorative objects.
Zircon: A Stone of Many Colors
Zircon is a versatile gemstone that can be found in a wide range of colors, from brilliant blue to green, yellow, brown, and even red. The blue variety of zircon is particularly prized for its bright, sparkling appearance. This color is usually achieved through heat treatment, which enhances the gem's natural properties.
Zircon has a long history of use in jewelry, particularly in the Middle Ages. During this period, zircon was believed to have the power to lull the wearer into a deep sleep and protect them from evil spirits. These beliefs were likely influenced by the gem's luminous quality and its ability to refract light.
Zircon is also associated with ancient civilizations, including those in India and Southeast Asia. It was often used in sacred rituals and was believed to bring wisdom and insight. Today, zircon is appreciated not only for its historical significance but also for its affordability and brilliance, making it a popular choice for everyday jewelry.
Zircon is found in various parts of the world, including Sri Lanka, Australia, Myanmar, Vietnam, and Cambodia. These regions also overlap with sapphire sources, which is not uncommon, as both gems share similar geological conditions.
Blue Topaz: A Symbol of Strength and Clarity
Blue topaz is a gemstone that ranges in color from a pale sky blue to a deep, vibrant Swiss blue and even a darker London blue. It is known for its clarity and brilliance, which make it a popular choice for a variety of jewelry pieces. Blue topaz is also believed to have spiritual and emotional benefits, such as increasing inner strength, cultivating the intellect, and enhancing creativity.
The symbolism of blue topaz includes love, beauty, and wisdom. It is often used in rings, pendants, and earrings, and its affordability makes it an accessible option for those who want to wear a December birthstone without the high cost associated with rarer gems.
Blue topaz was added to the list of December birthstones to provide a modern alternative to the more traditional turquoise and zircon. Its popularity has grown in recent years, thanks to its vibrant colors and the ease with which it can be cut and polished.
Geological Formation and Sources
Tanzanite: A Unique Geological Phenomenon
Tanzanite is a metamorphic gemstone that is found only in the Merelani Hills of northern Tanzania. It is formed when the mineral zoisite undergoes a transformation under high pressure and heat. The deep blue-violet colors of tanzanite are the result of a process called irradiation, which is often used in the enhancement of the gemstone to bring out its full color.
The Merelani Hills are located near Mount Kilimanjaro, and the mining operations there are among the most extensive in the world. The region's unique geological conditions have resulted in the formation of some of the largest and most valuable tanzanite crystals ever found. The scarcity of this gemstone, combined with its beauty, ensures that it remains a highly sought-after stone in the global market.
Turquoise: A Precipitate of Time
Turquoise is a hydrated phosphate of aluminum and copper, which is formed through a process of chemical precipitation. It is typically found in arid regions where copper deposits have been exposed to surface weathering. The stone is often found in association with other minerals, such as quartz, calcite, and pyrite.
The most famous turquoise deposits are located in Iran, where the deep blue "Persian blue" turquoise is still highly valued. In the United States, Arizona and Nevada are the primary sources of turquoise, with the Kingman and Sleeping Beauty mines being historically important. China has also become a major producer of turquoise, with Hubei Province being the main source of gem-quality material.
Turquoise is known for its relatively low hardness, which ranges from 5 to 6 on the Mohs scale. This means that it is relatively soft and can be easily damaged by acids, heat, and other harsh chemicals. As a result, many turquoise stones are treated to improve their durability and appearance. These treatments can include dyeing, resin impregnation, and cavity filling.
Zircon: A Versatile and Durable Gem
Zircon is a silicate mineral that is found in a variety of colors, including blue, green, yellow, brown, and red. The blue variety of zircon is particularly popular and is often produced through heat treatment. Zircon is known for its high refractive index, which gives it a brilliant, glassy luster.
Zircon is found in various parts of the world, including Sri Lanka, Australia, Myanmar, Vietnam, and Cambodia. These regions also overlap with sapphire sources, which is not uncommon, as both gems share similar geological conditions. Zircon's versatility and affordability have made it a popular choice for jewelry, particularly in the form of rings and pendants.
The hardness of zircon ranges from 6 to 7.5 on the Mohs scale, making it a relatively durable gemstone. However, some heat-treated zircon stones may revert to their original colors after prolonged exposure to bright light. As a result, it is important to care for zircon properly to maintain its color and brilliance.
Blue Topaz: A Colorful Transformation
Blue topaz is a variety of topaz that is known for its beautiful blue colors, ranging from a pale sky blue to a deep, vibrant Swiss blue and even a darker London blue. The blue color of topaz is usually the result of irradiation and heat treatment, which are used to enhance the gemstone's natural properties.
Blue topaz is found in various parts of the world, including Brazil, Nigeria, and the United States. It is a relatively abundant gemstone, which makes it more affordable than other blue gemstones such as sapphires and tanzanite. The clarity and brilliance of blue topaz make it a popular choice for a variety of jewelry pieces, including rings, pendants, and earrings.
Gemological Properties
Tanzanite: A Vibrant and Rare Gem
Tanzanite is known for its deep, velvety blue-violet color, which is the result of a unique geological process. It is a relatively soft gemstone, with a hardness of 6 to 6.5 on the Mohs scale. This means that it can be easily scratched and should be handled with care. Tanzanite is also known for its high refractive index, which gives it a brilliant, glassy luster.
The chemical formula of tanzanite is CaAl₂(SiO₄)(OH)₂, which is the same as zoisite. However, the blue color of tanzanite is the result of a process called irradiation, which is used to enhance the gemstone's natural properties. Tanzanite is also known for its pleochroism, which means that it can display different colors when viewed from different angles.
Turquoise: A Soft and Delicate Gem
Turquoise is a relatively soft gemstone, with a hardness of 5 to 6 on the Mohs scale. This means that it can be easily scratched and should be handled with care. The chemical formula of turquoise is Al₂(SO₄)₃·(OH)₃·4H₂O, which is a hydrated phosphate of aluminum and copper.
Turquoise is known for its unique blue-to-green color, which is the result of its chemical composition. The presence of copper gives it its blue color, while the presence of iron gives it its green color. Turquoise is also known for its ability to absorb oils and other substances, which can cause it to change color over time.
Zircon: A Durable and Brilliant Gem
Zircon is a silicate mineral that is found in a variety of colors, including blue, green, yellow, brown, and red. The blue variety of zircon is particularly popular and is often produced through heat treatment. Zircon is known for its high refractive index, which gives it a brilliant, glassy luster.
The hardness of zircon ranges from 6 to 7.5 on the Mohs scale, making it a relatively durable gemstone. However, some heat-treated zircon stones may revert to their original colors after prolonged exposure to bright light. As a result, it is important to care for zircon properly to maintain its color and brilliance.
Blue Topaz: A Colorful and Affordable Gem
Blue topaz is a variety of topaz that is known for its beautiful blue colors, ranging from a pale sky blue to a deep, vibrant Swiss blue and even a darker London blue. The blue color of topaz is usually the result of irradiation and heat treatment, which are used to enhance the gemstone's natural properties.
Blue topaz is found in various parts of the world, including Brazil, Nigeria, and the United States. It is a relatively abundant gemstone, which makes it more affordable than other blue gemstones such as sapphires and tanzanite. The clarity and brilliance of blue topaz make it a popular choice for a variety of jewelry pieces, including rings, pendants, and earrings.
Symbolism and Metaphysical Beliefs
Tanzanite: A Stone of Insight and Spiritual Awakening
Tanzanite is believed to bring insight and spiritual awakening to its wearer. It is often associated with the third eye chakra, which is the center of intuition and wisdom. Tanzanite is also believed to promote emotional healing and to help individuals overcome fears and anxieties.
The deep, velvety blue-violet colors of tanzanite are thought to represent the night sky, symbolizing mystery, depth, and the infinite. Tanzanite is also associated with the 24th wedding anniversary, making it a meaningful choice for couples who want to celebrate their union with a unique and beautiful gemstone.
Turquoise: A Stone of Protection and Good Fortune
Turquoise is one of the oldest known gemstones and has been associated with protection and good fortune for thousands of years. In ancient Egypt, it was believed to have protective powers and was often used in amulets and jewelry to ward off evil spirits and bring good luck.
Turquoise is also associated with health, peace, and prosperity. In Native American cultures, it was used in ceremonial objects and jewelry to symbolize spiritual connection and protection. Turquoise rings were also exchanged in European traditions as tokens of affection, while in Tibet, the gem is considered a national treasure.
Zircon: A Stone of Lull and Protection
Zircon is believed to have the power to lull the wearer into a deep sleep and to protect them from evil spirits. These beliefs were particularly strong during the Middle Ages, when zircon was used in amulets and charms to provide protection and bring wisdom.
Zircon is also associated with ancient civilizations, including those in India and Southeast Asia. It was often used in sacred rituals and was believed to bring insight and spiritual connection. Today, zircon is appreciated not only for its historical significance but also for its affordability and brilliance, making it a popular choice for everyday jewelry.
Blue Topaz: A Stone of Strength and Clarity
Blue topaz is believed to increase inner strength, cultivate the intellect, and enhance creativity. It is also associated with love, beauty, and wisdom. The symbolism of blue topaz makes it a meaningful choice for those who want to wear a gemstone that represents their inner qualities and aspirations.
Blue topaz is also believed to bring clarity and focus, making it a popular choice for those who want to improve their mental and emotional well-being. The vibrant colors of blue topaz are thought to represent the sky and the sea, symbolizing freedom, adventure, and the infinite possibilities of life.
Care and Cleaning
Tanzanite: Gentle Handling for a Vibrant Gem
Tanzanite is a relatively soft gemstone, with a hardness of 6 to 6.5 on the Mohs scale. This means that it can be easily scratched and should be handled with care. Tanzanite is also sensitive to heat and chemicals, so it should be kept away from harsh detergents, solvents, and other abrasive substances.
To clean tanzanite jewelry, it is recommended to use a soft brush and mild soap in warm water. Ultrasonic and steam cleaners should be avoided, as they can damage the gemstone's surface. Tanzanite should also be stored separately from other gemstones to prevent scratches and other damage.
Turquoise: Delicate Care for a Timeless Gem
Turquoise is a relatively soft gemstone, with a hardness of 5 to 6 on the Mohs scale. This means that it can be easily scratched and should be handled with care. Turquoise is also sensitive to heat, chemicals, and oils, so it should be kept away from harsh detergents, solvents, and other abrasive substances.
To clean turquoise jewelry, it is recommended to use a soft brush and mild soap in warm water. Ultrasonic and steam cleaners should be avoided, as they can damage the gemstone's surface. Turquoise should also be stored separately from other gemstones to prevent scratches and other damage.
Zircon: Proper Handling for a Durable Gem
Zircon is a relatively durable gemstone, with a hardness of 6 to 7.5 on the Mohs scale. However, some heat-treated zircon stones may revert to their original colors after prolonged exposure to bright light. As a result, it is important to care for zircon properly to maintain its color and brilliance.
To clean zircon jewelry, it is recommended to use a soft brush and mild soap in warm water. Ultrasonic and steam cleaners should be avoided, as they can damage the gemstone's surface. Zircon should also be stored separately from other gemstones to prevent scratches and other damage.
Blue Topaz: Easy Care for a Vibrant Gem
Blue topaz is a relatively durable gemstone, with a hardness of 8 on the Mohs scale. This means that it can withstand normal wear and tear and does not require special handling. However, it is still important to care for blue topaz properly to maintain its color and brilliance.
To clean blue topaz jewelry, it is recommended to use a soft brush and mild soap in warm water. Ultrasonic and steam cleaners can also be used, as they will not damage the gemstone's surface. Blue topaz should also be stored separately from other gemstones to prevent scratches and other damage.
Conclusion
December is a month rich in symbolism and celebration, and its four birthstones—tanzanite, turquoise, zircon, and blue topaz—each carry their own unique history, properties, and significance. Tanzanite, a modern marvel discovered in Tanzania, is known for its deep, velvety blue-violet hues and is associated with insight and spiritual awakening. Turquoise, an ancient gemstone, has been cherished for thousands of years for its protective powers and symbolic meaning of health and good fortune. Zircon, with its brilliant blue color and versatility, has been used in jewelry and sacred rituals for centuries. Blue topaz, a vibrant and affordable gemstone, is believed to increase inner strength, cultivate the intellect, and enhance creativity.
Each of these December birthstones has its own geological formation and source, making them unique in their properties and characteristics. Tanzanite is found exclusively in the Merelani Hills of Tanzania, while turquoise is found in regions such as Iran, the United States, and China. Zircon is found in various parts of the world, including Sri Lanka and Australia, and blue topaz is found in countries such as Brazil and the United States.
The gemological properties of these stones vary, with tanzanite being relatively soft and requiring gentle handling, while blue topaz is more durable and can withstand normal wear and tear. Each gemstone has its own care and cleaning requirements, which should be followed to maintain their beauty and longevity.
In conclusion, the December birthstones offer a diverse and beautiful selection of gems that reflect the richness of the month. Whether you are a gemstone enthusiast, a jewelry buyer, or a student of gemology, these stones provide a fascinating glimpse into the history, science, and cultural significance of gemstones.