December, the final month of the year, is adorned with a unique distinction in the world of gemology. Unlike other months that are represented by a single birthstone, December is the only month with three official birthstones: tanzanite, turquoise, and zircon—specifically the blue zircon variety. This triad of gemstones, each with its own distinct color, history, and significance, makes December’s birthstones particularly rich in cultural and geological depth.
This article delves into the characteristics, historical significance, symbolism, and care tips for these three December birthstones, drawing from a range of authoritative and contemporary sources. Whether you are a gemstone enthusiast, a jewelry buyer, or simply curious about the origins and meanings behind these gems, this article offers an in-depth exploration of the December birthstones.
Introduction
The tradition of birthstones is a fascinating blend of ancient lore and modern gemological practice. It began with early civilizations that believed gemstones held mystical powers and could influence the wearer's fortune, health, and emotions. Over time, this belief evolved into a cultural tradition where each month of the year is associated with a specific gemstone. December, in particular, has an especially rich and varied history of birthstones.
The current list of December birthstones—tanzanite, turquoise, and blue zircon—was not always fixed. The selection has changed over the centuries, reflecting shifts in both scientific understanding and cultural practices. For example, ruby and lapis lazuli were once included in earlier versions of the December birthstone list. This evolution highlights the dynamic nature of birthstone traditions, which continue to adapt to new discoveries and changing tastes.
This article will explore the history and symbolism of each of these three December birthstones, their geological properties, and practical advice for caring for them. By the end, you will have a comprehensive understanding of why these stones are cherished not only for their beauty but also for their historical and cultural significance.
History and Lore of December Birthstones
The Evolution of the December Birthstone List
The history of December’s birthstones is marked by several key changes over the past century. In ancient times, ruby was considered one of the primary birthstones for December. It was believed to sharpen the mind and encourage courtly love, according to some historical sources. However, ruby eventually fell out of the list, making way for other gems that were either newly discovered or gaining popularity.
In the early 20th century, the National Association of Jewellers (now Jewellers of America) listed turquoise as the primary December birthstone, with lapis lazuli as an alternative. This arrangement lasted until 1952, when zircon, particularly blue zircon, was added to the list by the Jewelry Industry Council of America. Zircon brought with it a new range of symbolic meanings, including emotional balance and joy.
In 2002, tanzanite, a relatively new gemstone discovered in 1967 in Tanzania, was officially added to the December birthstone list in the United States. This addition brought the total number of December birthstones to three, a distinction that remains to this day.
These changes reflect not only the evolving tastes of the jewelry industry but also the growing appreciation for newly discovered gemstones and their unique properties.
Cultural and Symbolic Significance
Each of the December birthstones carries its own set of cultural and symbolic meanings. Turquoise, for example, has been used for thousands of years across various civilizations. In ancient Egypt, it was a symbol of protection and was often inlaid in royal jewelry. It was believed to bring health and good fortune, and in some cultures, it was thought to protect the wearer from falls, especially while riding horses.
Zircon, particularly the blue variety, has been associated with emotional balance and joy. In some traditions, it is believed to bring a quiet, calming energy to the wearer. Before 1952, lapis lazuli was the December birthstone in some regions. It was favored by ancient royalty and artists for its deep blue color and was considered a stone of self-mastery and protection.
Tanzanite, the most modern of the three, has quickly become a favorite due to its vivid blue to violet hues. It is known as a protective and soothing stone that helps the wearer communicate spiritual truths in a calm and clear manner.
These symbolic associations have contributed to the enduring popularity of these gemstones in jewelry and spiritual practices alike.
Geological Formation and Sources
Tanzanite
Tanzanite is a relatively rare gemstone, found almost exclusively in the Merelani Hills of Tanzania, near the border with Kenya. It was first discovered in 1967 and was brought to international attention by the Tiffany & Co. jewelry house, which marketed it as a December birthstone.
Geologically, tanzanite is a variety of the mineral cushionite, which is a type of zircon. It forms in metamorphic rocks under specific temperature and pressure conditions. Most tanzanite begins as a brownish zoisite, which is heat-treated to produce the beautiful blue to violet hues that characterize the gemstone. This heat treatment is stable and permanent, making the color safe for jewelry use.
Tanzanite is rated at 6 to 7 on the Mohs scale of hardness, which means it is relatively durable but not as hard as diamonds or sapphires. It is also sensitive to sudden temperature changes and strong acids, such as hydrochloric and hydrofluoric acids, which can damage the stone.
Turquoise
Turquoise is a phosphate mineral composed of copper and aluminum. It forms in the oxidized zones of copper deposits, typically in arid regions. The most well-known sources of turquoise include Nevada, Arizona, and New Mexico in the United States, as well as Iran (Persia), China, and Egypt.
Turquoise is known for its semi-translucent to opaque appearance, with a color range from blue to green, depending on the presence of copper and iron. It often contains veins of matrix, which are remnants of the surrounding rock. These matrix patterns can add to the stone’s visual appeal and are often preserved in jewelry.
Turquoise is relatively soft, with a Mohs hardness of 5 to 6, and it is also porous, which makes it susceptible to damage from oils, lotions, and harsh chemicals. It is best stored in a dry environment and should be cleaned gently to avoid scratching or discoloration.
Zircon
Zircon is a mineral that has been known for thousands of years, but it has only recently gained recognition as a December birthstone. It is found in a wide range of colors, including blue, red, brown, and green, depending on the trace elements and heat treatment it undergoes.
Blue zircon, the most common variety associated with December, is typically heat-treated to enhance its color. This variety is often found in Brazil, Vietnam, Australia, and Zambia. Zircon is a relatively hard gemstone, with a Mohs hardness of 6.5 to 7.5, making it more durable than turquoise but not as hard as tanzanite.
Zircon is also notable for its high refractive index and strong dispersion, which gives it a sparkling, diamond-like appearance. This makes it a popular alternative to diamonds in jewelry.
Gemological Properties
| Gemstone | Color | Mohs Hardness | Chemical Composition | Origin (Primary) | Treatments | Durability Notes |
|---|---|---|---|---|---|---|
| Tanzanite | Blue to violet | 6–7 | Calcium aluminum silicate | Tanzania | Heat-treated | Sensitive to acids and temperature changes |
| Turquoise | Blue to green | 5–6 | Hydrated phosphate of copper/Al | USA, Iran, Egypt | None | Soft and porous; avoid moisture and oils |
| Blue Zircon | Blue | 6.5–7.5 | Zirconium silicate | Brazil, Vietnam, Zambia | Heat-treated | High dispersion; durable for jewelry |
Key Characteristics
Tanzanite
- Color: Tanzanite is known for its rich blue to violet hues, which are enhanced through heat treatment.
- Hardness: It has a Mohs hardness of 6 to 7, making it suitable for jewelry, though not ideal for daily wear in rings.
- Chemistry: Tanzanite is a trigonal mineral and is a form of cushionite, a type of zircon.
- Durability: While it is relatively durable, it can be damaged by sudden temperature changes or strong acids.
Turquoise
- Color: Turquoise ranges from blue to green, depending on the presence of copper and iron.
- Hardness: With a Mohs hardness of 5 to 6, it is relatively soft and porous, making it sensitive to oils and lotions.
- Chemistry: It is a phosphate mineral and is hydrated, which affects its stability.
- Durability: It is best suited for low-wear jewelry such as pendants and earrings.
Blue Zircon
- Color: Blue zircon is known for its vibrant blue color, often achieved through heat treatment.
- Hardness: It has a Mohs hardness of 6.5 to 7.5, making it more durable than turquoise but less than tanzanite.
- Chemistry: Zircon is a zirconium silicate, and it has a high refractive index, giving it a sparkling appearance.
- Durability: It is very durable and is often used as a diamond simulant in jewelry.
These properties not only determine how each gemstone is used in jewelry but also how it should be stored and cleaned to maintain its beauty and integrity.
Symbolism and Metaphysical Beliefs
Tanzanite
Tanzanite is often described as a stone of transformation and spiritual healing. It is believed to help the wearer open the heart and communicate spiritual truths in a calm and compassionate manner. It is also considered a soothing stone that can help reduce stress and emotional turbulence.
In some metaphysical traditions, tanzanite is said to enhance intuition and inner vision, making it a popular choice for those seeking spiritual clarity.
Turquoise
Turquoise has long been associated with protection, luck, and good fortune. In ancient Egypt, it was used in amulets and jewelry to ward off evil and bring health to the wearer. In the Middle East and North Africa, it was believed to protect the wearer from falling, especially from horses.
In Native American traditions, turquoise is considered a stone of the sky, symbolizing healing, truth, and divine connection. It is often used in ceremonial jewelry and spiritual practices.
Blue Zircon
Blue zircon is known for its calming and balancing properties. It is believed to help the wearer achieve emotional stability and inner peace. It is also associated with joy and optimism, making it a popular choice for those seeking emotional upliftment.
In some traditions, zircon is considered a stone of the heart, helping to open the heart chakra and promote love and compassion.
These metaphysical beliefs, while not scientifically proven, continue to influence the spiritual and emotional use of these gemstones in various cultures and practices.
Care and Cleaning
Tanzanite
Tanzanite is relatively durable but requires gentle care to maintain its appearance and integrity.
- Cleaning: Use warm, soapy water and a soft cloth or brush. Avoid using ultrasonic or steam cleaners, as these can damage the stone.
- Storage: Store tanzanite in a soft cloth or padded compartment to prevent scratches.
- Avoid: Exposure to strong acids, sudden temperature changes, and harsh chemicals.
Tanzanite is best set in pendants or earrings, as these settings reduce the risk of impact damage. While it can be used in rings, it is not recommended for daily wear due to its relative softness.
Turquoise
Turquoise is a delicate gemstone that requires special care to preserve its color and structure.
- Cleaning: Clean with a soft, damp cloth and a mild soap solution. Avoid using ultrasonic cleaners, steam cleaners, or abrasive materials.
- Storage: Store turquoise in a dry, cool place. Avoid direct sunlight and moisture, as these can alter the color and cause cracking.
- Avoid: Oils, lotions, and perfumes, as these can stain or dull the surface of the stone.
Turquoise is best suited for low-wear jewelry, such as pendants and earrings. It is not recommended for rings or other pieces that are subject to daily impact.
Blue Zircon
Blue zircon is a relatively durable gemstone that can be cleaned and maintained with minimal effort.
- Cleaning: Use warm, soapy water and a soft cloth or brush. Zircon can also be cleaned with an ultrasonic cleaner, as it is less sensitive to this method than many other gemstones.
- Storage: Store zircon in a dry, secure location to avoid scratches or damage.
- Avoid: Exposure to extreme heat, which can alter the color of the stone.
Zircon is a versatile gemstone that can be used in rings, pendants, and earrings. Its sparkling appearance and durability make it an excellent choice for everyday wear.
Conclusion
December’s three birthstones—tanzanite, turquoise, and blue zircon—offer a fascinating blend of beauty, history, and symbolism. Each stone has its own unique properties and meanings, making them valuable not only as jewelry but also as symbols of personal and spiritual significance.
Tanzanite, with its vibrant blue to violet hues, represents transformation and spiritual clarity. Turquoise, a gemstone of ancient tradition, is known for its protective qualities and connection to the divine. Blue zircon, a sparkling gemstone, brings emotional balance and joy.
Whether you are choosing a December birthstone for yourself or as a gift, these gems offer a rich tapestry of meaning and beauty. With proper care and appreciation, they can be enjoyed for a lifetime, serving as testaments to the enduring allure of gemstones.