Tanzanite, the captivating blue to violet gemstone, is one of the most fascinating additions to the world of birthstones. Discovered relatively recently in 1967, tanzanite quickly captured the attention of jewelers and collectors with its rich color and rarity. Named in honor of its country of origin, Tanzania, this gemstone is found exclusively in a small region near Mount Kilimanjaro. As a December birthstone, tanzanite symbolizes transformation and renewal, making it a meaningful and beautiful choice for those born in the final month of the year.
This article delves into the history of tanzanite, its geological formation, gemological properties, and its cultural significance. It also provides practical guidance on how to care for this delicate gemstone. The information is drawn exclusively from authoritative sources, ensuring accuracy and reliability.
History and Lore
Tanzanite’s journey to becoming a recognized gemstone is as intriguing as the gem itself. Before 1967, the mineral zoisite, of which tanzanite is a variety, was well known to mineralogists but had not yet been discovered in its stunning blue-violet form. The story of tanzanite’s discovery is often attributed to a Maasai tribesman who found the first specimens in the Merelani Hills of northern Tanzania. These stones were initially mistaken for sapphires due to their intense blue color.
The discovery was soon brought to the attention of Manuel d’Souza, an Indian prospector known for his global search for precious stones. D’Souza, often referred to as “Mad Manuel,” quickly registered mining claims in the area. As the mining operations expanded, it became clear that these were not sapphires, but a new and previously unknown variety of zoisite. This realization sparked interest among gemologists, and the mineral was eventually identified as a distinct gemstone.
Tanzanite’s name was suggested by the marketing team at Tiffany & Co., who recognized the gem’s potential. They understood that naming it “blue zoisite” might not be appealing due to its resemblance to the phrase “blue suicide.” Instead, they chose to honor the country of origin by naming it tanzanite. This decision proved to be a masterstroke, as tanzanite quickly became a sensation in the jewelry world. By 1968, Tiffany & Co. launched a major advertising campaign to promote the gemstone, highlighting its vibrant colors and unique origin.
The gemstone’s popularity continued to grow, and by 2002, tanzanite was officially recognized as a December birthstone. This addition was a significant milestone, as December previously had three other birthstones: turquoise, blue topaz, and zircon. Tanzanite’s inclusion brought a new level of color and character to the month’s list of gemstones. Today, tanzanite is not only a December birthstone but also the gemstone associated with the 24th wedding anniversary.
Geological Formation and Sources
Tanzanite is a unique gemstone in that it is found in only one place on Earth: the Merelani Hills in northern Tanzania. This region, located near Mount Kilimanjaro, is the sole commercial source for tanzanite. The geological conditions in this area are ideal for the formation of tanzanite, which is a variety of the mineral zoisite.
The formation of tanzanite involves a combination of specific mineral composition and environmental factors. Zoisite, the parent mineral, is typically found in metamorphic rocks, which are formed from the transformation of existing rock types under intense heat and pressure. The presence of vanadium in the geological matrix, along with extreme heat, contributes to the development of tanzanite’s characteristic blue-violet color. This color is further enhanced through heat treatment, which is a common practice in the gemstone industry to bring out the most desirable hues.
The Merelani Hills, where tanzanite is mined, cover an area of just a few square kilometers. This limited geographical distribution is a key factor in the gemstone’s rarity. Mining operations in the region involve digging more than 100 meters into the earth, with thousands of workers involved in the extraction process. The landscape is characterized by grass-covered hillsides, scrub brush, and rocky soil, with the towering presence of Mount Kilimanjaro adding to the region’s dramatic scenery.
Despite its limited availability, tanzanite has a relatively short history as a commercial gemstone. The first large-scale mining operations began in the late 1960s, and the gemstone quickly gained international attention. However, the supply of tanzanite remains constrained, and many of the mines in the region are now producing at a reduced capacity. This scarcity contributes to the gemstone’s value and makes it an especially sought-after choice for collectors and jewelry enthusiasts.
Gemological Properties
Tanzanite is distinguished by its deep blue to violet color, which is often described as "velvety" due to its saturated and rich appearance. This coloration is a result of the gemstone's pleochroism, a property that allows it to display different colors when viewed from different angles. In its natural state, tanzanite can appear brown or green, but heat treatment is used to enhance its blue and violet hues, which are considered the most valuable.
The gemstone's chemical composition is based on the mineral zoisite, which has the formula Ca₂Al₃(SiO₄)(Si₂O₇)O(OH). The presence of vanadium in the crystal structure is responsible for the blue-violet coloration. Tanzanite is typically found in nature as colorless, brown, pink, or green, but it is the heat-treated blue-violet variety that is most commonly used in jewelry.
In terms of hardness, tanzanite measures between 6.0 and 7.0 on the Mohs Hardness Scale. This places it in the lower to middle range of gemstone hardness, making it more susceptible to scratches and abrasions compared to harder stones like sapphires or diamonds. Due to its relative softness, tanzanite is best suited for jewelry that is not worn daily, such as earrings and pendants. It is not recommended for rings that are worn frequently, as the gemstone can be easily damaged.
Tanzanite is also known for its high clarity and potential for large cut stones. The gemstone can be cut into a variety of shapes, including traditional round and princess cuts, as well as more unique shapes like emerald or cushion cuts. Skilled lapidaries can carve or sculpt tanzanite into intricate designs, making it a versatile choice for jewelry.
One of the most notable characteristics of tanzanite is its pleochroism, which allows it to display different colors when viewed from different angles. This property requires careful cutting to ensure that the most desirable blue and violet hues are emphasized. When cut correctly, tanzanite can rival the beauty of sapphires and other blue gemstones.
Symbolism and Metaphysical Beliefs
Tanzanite is often associated with transformation, intuition, and emotional healing. These symbolic meanings have contributed to its popularity not only as a birthstone but also as a gemstone used in metaphysical practices. The deep blue and violet hues of tanzanite are believed to resonate with the throat and third eye chakras, which are associated with communication and spiritual insight.
In ancient times, blue stones were often revered for their perceived ability to enhance spiritual awareness and promote emotional balance. While tanzanite is a relatively modern discovery, it has quickly adopted many of the symbolic meanings associated with other blue gemstones. It is believed to help individuals access their inner wisdom and encourage emotional clarity.
In addition to its spiritual properties, tanzanite is also associated with protection and renewal. Its rarity and the fact that it is found only in Tanzania have led to the belief that it carries a unique energy that is tied to its geographic origin. Some people believe that wearing tanzanite can help them connect with the natural world and tap into the healing energies of the Earth.
Tanzanite is also considered a gemstone of the 24th wedding anniversary, symbolizing enduring love and commitment. This makes it a meaningful choice for couples looking to celebrate their milestone anniversary with a piece of jewelry that carries both emotional and symbolic significance.
Care and Cleaning
Given its relative softness and sensitivity to temperature changes, tanzanite requires special care to maintain its beauty and integrity. While it is resistant to the effects of normal heat, light, and common chemicals, it can be damaged if exposed to very high temperatures or sudden temperature changes. It is also vulnerable to scratches and abrasions, which can diminish its appearance over time.
To clean tanzanite, it is recommended to use warm, soapy water and a soft cloth. Ultrasonic and steam cleaners should be avoided, as they can cause damage to the gemstone. When storing tanzanite jewelry, it is best to keep each piece separately in a soft cloth or padded container to prevent scratches. This is especially important when storing tanzanite with harder gemstones like diamonds or sapphires, which can scratch its surface.
Tanzanite is best suited for jewelry that is not worn daily, such as earrings and pendants. While it can be worn in rings, a protective mounting is recommended to minimize the risk of damage. With proper care, tanzanite can be a beautiful and enduring gemstone that retains its brilliance for years to come.
Conclusion
Tanzanite is a remarkable gemstone that combines rarity, beauty, and symbolic significance. Discovered in the late 1960s in the Merelani Hills of Tanzania, it quickly became a sensation in the world of jewelry. Its deep blue to violet color, enhanced through heat treatment, makes it a stunning choice for those born in December or those celebrating a 24th wedding anniversary.
As a December birthstone, tanzanite represents transformation and renewal, making it a meaningful and personal choice for individuals seeking a gemstone with both aesthetic and emotional value. Its geological rarity, found only in a small region near Mount Kilimanjaro, adds to its allure and makes it a highly sought-after gemstone among collectors and jewelry enthusiasts.
Despite its relative softness, tanzanite is a durable gemstone when properly cared for. It is best suited for jewelry that is worn on special occasions, such as earrings and pendants, and should be stored carefully to prevent scratches and damage. With its vibrant colors, unique origin, and symbolic meanings, tanzanite continues to captivate and inspire those who appreciate the beauty and history of gemstones.