December boasts a remarkable selection of birthstones, but among them, tanzanite stands out as the newest and arguably most sensational addition. Officially recognized in 2002, this vibrant blue-violet gemstone quickly captivated the world, earning the moniker “Gem of the 20th Century.” This article will delve into the history, geological origins, gemological properties, and significance of tanzanite, exploring its journey from a recent discovery to a celebrated December birthstone.
History and Lore
For centuries, December was traditionally associated with turquoise, blue zircon, and blue topaz as its birthstones. However, the landscape shifted in the latter half of the 20th century with the introduction of tanzanite. The story begins in the late 1960s in the foothills of Mount Kilimanjaro in Tanzania. A Maasai tribesman named Jumanne Ngoma is credited with the initial discovery of the strikingly colored crystals. Initially mistaken for sapphires, the gems were brought to the attention of prospector Manuel d’Souza, who subsequently shared them with gemologists for identification.
The Gemological Institute of America (GIA) determined that these were not sapphires, but a previously unknown variety of the mineral zoisite. Recognizing its potential, Tiffany & Co. took a keen interest in marketing the gemstone. However, a significant hurdle arose: the name “blue zoisite” bore an unfortunate resemblance to “blue suicide,” a potentially disastrous association for a marketing campaign. To overcome this, Tiffany & Co. strategically rebranded the gem as “tanzanite,” a name that honored its Tanzanian origin and resonated with a sense of exotic allure.
The introduction of tanzanite as a December birthstone in 2002 by the Jewelers of America marked a rare addition to the established birthstone list, which hadn’t been amended since 1912. This event underscored the gem’s growing popularity and solidified its place in the world of colored gemstones. Today, it is also recognized as the gem for the 24th wedding anniversary.
Geological Formation and Sources
Tanzanite’s unique geological story contributes to its rarity and value. The gemstone is found in a very limited geographical area – a small mining zone near the Mererani Hills of northern Tanzania, close to Mount Kilimanjaro. This restricted source makes tanzanite significantly rarer than many other gemstones. It is formed within a complex geological environment involving intense heat and pressure, and the presence of vanadium, which contributes to its distinctive blue-violet color.
The gem is a blue variety of the mineral zoisite, a calcium aluminum silicate. The specific conditions required for its formation are exceptionally localized, leading geologists to believe that tanzanite deposits are unlikely to be found anywhere else in the world. This singular origin further enhances its desirability and value.
Gemological Properties
Tanzanite exhibits a range of fascinating gemological properties. While often described as blue, its color can vary from deep blue to violet-blue, and even lavender. This pleochroism – the ability to display different colors when viewed from different angles – is a characteristic feature of tanzanite.
Key gemological properties include:
- Chemical Formula: Ca2Al3(SiO4)3(OH)
- Color: Blue, violet-blue, lavender
- Crystal System: Triclinic
- Hardness (Mohs Scale): 6.5 – 7 (relatively soft, requiring careful handling)
- Cleavage: Perfect in one direction, making it somewhat brittle.
- Refractive Index: 1.655 – 1.676
- Specific Gravity: 3.35 – 3.50
The gem’s brilliance and clarity are also notable. High-quality tanzanite specimens often exhibit excellent clarity, allowing light to pass through with minimal obstruction. Larger cut stones are particularly prized, adding to the gem’s allure. Blue Topaz, while also a December birthstone, possesses a glass-like shine and a fine cleavage, making it more delicate than tanzanite. Zircon, another December birthstone, is celebrated for its fire and range of colors, and is one of the oldest minerals on Earth.
Symbolism and Metaphysical Beliefs
While the sources do not detail extensive metaphysical beliefs specifically associated with tanzanite, December birthstones in general are known for their symbolism. December’s birthstones, including tanzanite, are often associated with qualities like serenity, wisdom, and good fortune. The vibrant blue hues are thought to represent calmness and tranquility.
More broadly, birthstones are believed to hold unique energies and properties that can positively influence the wearer’s life. The tradition of wearing birthstones dates back to ancient times, with each gem believed to offer protection, healing, and spiritual benefits. The association of tanzanite with December, a time often associated with reflection and renewal, further enhances its symbolic significance.
Care and Cleaning
Due to its hardness of 6.5 to 7 on the Mohs scale, tanzanite is relatively soft and requires careful handling. It also possesses perfect cleavage in one direction, making it susceptible to chipping or breaking if subjected to significant impact.
To maintain its beauty, tanzanite jewelry should be cleaned with warm, soapy water and a soft brush. Avoid harsh chemicals, ultrasonic cleaners, and steam cleaners, as these can damage the gemstone. It is also advisable to remove tanzanite jewelry before engaging in strenuous activities or when exposed to potential impacts. Regular cleaning and careful storage will help preserve the gem’s brilliance and prevent damage.
Conclusion
Tanzanite’s journey from a recent discovery in the foothills of Mount Kilimanjaro to a celebrated December birthstone is a testament to its exceptional beauty and rarity. Its unique geological origins, captivating color, and intriguing history have cemented its place in the world of gemstones. As a relatively new addition to the birthstone calendar, tanzanite offers a modern and vibrant alternative to traditional December gems, appealing to those seeking a unique and meaningful gemstone. Its limited supply and growing popularity ensure that tanzanite will continue to be treasured for generations to come.