Tanzanite, a captivating blue to violet gemstone, was officially recognized as a December birthstone in 2002. While it may seem like a relatively recent addition to the birthstone tradition, tanzanite quickly gained popularity due to its striking color, limited availability, and unique geological origins. Discovered in Tanzania in the late 1960s, tanzanite is the only gemstone that can only be found in one location on Earth — making it one of the rarest and most valuable gemstones in the world.
This article explores the history, geological properties, cultural significance, and care instructions for tanzanite. As we delve into the world of this extraordinary gemstone, we will uncover how it became a December birthstone, its unique formation process, and the reasons behind its enduring appeal.
History and Lore
The story of tanzanite begins in the late 1960s in the foothills of Mount Kilimanjaro in Tanzania. A local Maasai tribesman named Jumanne Ngoma was the first to discover the gemstone. Initially, the deep blue to violet crystals were mistaken for sapphires. However, when samples were examined by the Gemological Institute of America (GIA), they were identified as a new and previously unknown variety of the mineral zoisite.
Tiffany & Co. was the first major jewelry company to recognize the potential of this new gemstone. However, the marketing team at Tiffany faced a significant challenge: the name "blue zoisite" was difficult to pronounce and sounded too similar to "blue suicide," which could have negatively impacted its marketability. To overcome this hurdle, Tiffany decided to rename the gemstone "tanzanite," a name that would honor its country of origin and create a sense of exclusivity and prestige.
Tanzanite was officially designated as a December birthstone in 2002. This decision reflected the gemstone's growing popularity and its ability to complement the traditional December birthstones like turquoise, blue zircon, and blue topaz. The addition of tanzanite to the December birthstone list also highlighted the gemstone's connection to the 24th wedding anniversary, further expanding its significance in the world of jewelry.
Geological Formation and Sources
Tanzanite is a unique gemstone because it is only found in one place on Earth — the Merelani Hills in northern Tanzania. This limited source has contributed to its rarity and value. The gemstone is a variety of the mineral zoisite, with the chemical formula Ca₂Al₃(SiO₄)(OH)₃. What makes tanzanite particularly special is its trichroic nature, meaning it can display three different colors — blue, violet, and brown — depending on the angle from which it is viewed.
Tanzanite forms under specific geological conditions involving the metamorphism of limestone and other sedimentary rocks. The presence of vanadium and chromium is responsible for the gemstone's distinctive blue and violet hues. These elements are incorporated into the crystal lattice during the formation process, creating the vibrant colors that make tanzanite so desirable.
The Merelani Hills, where tanzanite is found, are part of a larger geological region known for its mineral wealth. The area is also known for producing other valuable minerals, including ruby, sapphire, and peridot. However, tanzanite remains the most famous gemstone from this region due to its rarity and the fact that it is only found in one place in the world.
Gemological Properties
Tanzanite is a relatively soft gemstone with a hardness of 6 to 6.5 on the Mohs scale. This means it is more susceptible to scratches and damage than harder gemstones like diamonds or sapphires. Despite its lower hardness, tanzanite is known for its excellent clarity and vibrant color. The gemstone is often found in large, well-formed crystals, which can be cut into a variety of shapes and sizes.
One of the most remarkable properties of tanzanite is its pleochroism — the ability to display different colors when viewed from different angles. This property is particularly noticeable in tanzanite because of the combination of blue, violet, and brown hues. The most desirable tanzanite stones are those that exhibit a deep blue or violet color when viewed from the top, with minimal brown coloration.
Tanzanite also has a relatively high refractive index, which contributes to its brilliance and fire. The gemstone is typically cut in a way that maximizes its color and clarity. Common cuts for tanzanite include the cushion cut, oval cut, and emerald cut. These cuts help to enhance the gemstone's natural beauty and make it suitable for a wide range of jewelry designs.
Symbolism and Metaphysical Beliefs
Tanzanite is not only valued for its physical properties but also for its symbolic and metaphysical significance. In many cultures, tanzanite is associated with wisdom, intuition, and spiritual growth. The gemstone is believed to enhance the wearer's ability to perceive truth and to communicate effectively. It is also thought to promote emotional healing and balance, making it a popular choice for those seeking inner peace and harmony.
In the realm of crystal healing, tanzanite is considered a powerful stone for opening the third eye and crown chakras. These chakras are associated with higher consciousness, spiritual awareness, and divine connection. By working with tanzanite, individuals are believed to gain greater insight into their lives and to develop a deeper understanding of themselves and the world around them.
Tanzanite is also associated with the 24th wedding anniversary, symbolizing deep love and enduring commitment. This connection further reinforces the gemstone's role as a meaningful and symbolic stone, making it a popular choice for engagement rings, anniversary jewelry, and other sentimental pieces.
Care and Cleaning
Given its relatively low hardness on the Mohs scale, tanzanite requires careful handling and cleaning to maintain its beauty and integrity. The gemstone should be stored separately from harder gemstones to prevent scratches. It is also advisable to avoid exposing tanzanite to extreme temperatures or harsh chemicals, as these can cause damage or discoloration.
When cleaning tanzanite, it is best to use a mild soap solution and a soft cloth or brush. Ultrasonic cleaners and steam cleaners should be avoided, as they can potentially damage the gemstone. After cleaning, tanzanite should be dried with a soft, lint-free cloth to prevent water spots.
Tanzanite is also sensitive to heat, so it is important to avoid exposing it to high temperatures for extended periods. This includes avoiding direct sunlight for long durations and refraining from using hot water for cleaning. Additionally, tanzanite should be removed before engaging in activities that may cause physical impact, such as sports or heavy manual labor.
Conclusion
Tanzanite is a remarkable gemstone that combines rarity, beauty, and symbolic meaning. As a December birthstone, it offers a unique and valuable addition to the traditional selection of blue gemstones like turquoise, blue zircon, and blue topaz. The gemstone's deep blue to violet color, trichroic nature, and limited availability make it highly desirable among gemstone enthusiasts and jewelry collectors.
Discovered in Tanzania in the late 1960s and officially designated as a December birthstone in 2002, tanzanite has quickly become a favorite among those who appreciate its vibrant color and spiritual significance. Its geological properties, including its hardness, refractive index, and pleochroism, contribute to its visual appeal and versatility in jewelry design.
Whether worn as a birthstone, an anniversary gemstone, or a symbol of spiritual growth, tanzanite continues to captivate and inspire. Its rarity and limited availability ensure that it remains a valuable and sought-after gemstone for generations to come.