For individuals born on December 28th, the gemstone associated with their birthdate is a relatively modern marvel of the mineral world: Tanzanite. This rare and captivating stone is known for its vibrant violet-blue color, its recent discovery in the foothills of Mount Kilimanjaro, and its deep symbolic meaning. As the December 28th birthstone, Tanzanite holds a unique place in the world of gemology, both for its geological rarity and its cultural significance. This article explores the history, gemological properties, symbolism, and care of Tanzanite, drawing from expert sources and reliable information to provide a comprehensive guide for gemstone enthusiasts, jewelry buyers, and students of gemology.
Tanzanite is the designated birthstone for those born on December 28th. Its discovery in the 1960s in the foothills of Mount Kilimanjaro in Tanzania marked a significant event in the world of gemstones. Unlike many other gemstones that have been known for centuries, Tanzanite is a relatively modern addition to the birthstone calendar. This gem has quickly gained popularity due to its unique color and its association with spiritual growth and transformation. Celebrated for its radiant hues, which range from deep violet-blue to rich purple, its color-changing properties make it a particularly intriguing gemstone, as it can appear different under various lighting conditions. For those born in December, and specifically on the 28th, Tanzanite is not just a birthstone but a symbol of individuality and the journey they embark upon each year.
History and Lore
The history of Tanzanite is remarkably short compared to other gemstones, which adds to its allure as a contemporary treasure. The gemstone was discovered relatively recently, in the 1960s, in the foothills of Mount Kilimanjaro in Tanzania. This specific location in the Merelani Hills is the only known source of this gemstone, making it one of the rarest gems on Earth. The discovery is often credited to a Maasai herder who found blue crystals in the region, though the gem was later brought to the attention of the international gem market. Its rapid ascent in popularity was facilitated by the gemstone and jewelry company Tiffany & Co., which recognized its potential and launched a marketing campaign in 1968, naming it after the country of its origin.
As a birthstone, Tanzanite is a modern addition. While December has multiple traditional birthstones, including Turquoise and Zircon, Tanzanite was officially recognized as a modern birthstone for December in 2002 by the American Gem Trade Association (AGTA). This inclusion expanded the options for those born in the month, offering a gem with a distinct and vivid color palette. For individuals born on December 28th, Tanzanite is specifically highlighted as their birthstone in various gemological and birthstone guides. Its status as a birthstone is not merely a matter of tradition but is also tied to its unique characteristics and the symbolic meanings it carries.
The lore surrounding Tanzanite, while brief, is rich with themes of transformation and spiritual awareness. Unlike ancient gemstones with centuries of folklore, Tanzanite’s symbolism is more aligned with contemporary metaphysical beliefs. It is often associated with the transformative energy of its discovery and its striking color change, which is seen as a metaphor for personal growth and new beginnings. As a birthstone for December 28th, it is believed to resonate with the personalities of those born on this date, who are often described as responsible and self-controlled, traits that can be complemented by the stone’s calming and insightful energies.
Geological Formation and Sources
Tanzanite’s geological origin is as unique as its color. It is a variety of the mineral zoisite, specifically the blue to violet form of the mineral, which is caused by the presence of vanadium and chromium. The gemstone is formed under specific geological conditions that are found only in a small area of Tanzania. The primary source is the Merelani Hills near Mount Kilimanjaro, which is currently the only commercial source of this gemstone. This extreme rarity, with geologists estimating that the source may be depleted within a few decades, adds to its value and desirability.
The formation of Tanzanite is a result of a unique geological event. The stones are found in alluvial deposits, which means they have been eroded from their original host rock and transported by water. The original formation is believed to have occurred during the metamorphism of the surrounding rocks, where heat and pressure transformed the original zoisite into its blue variety. The process that created the vibrant blue color is a rare coincidence of geological factors, making the existence of Tanzanite a geological anomaly. This limited geographic source means that all Tanzanite on the market comes from a single region, making it one of the most location-specific gemstones in the world.
The mining of Tanzanite is conducted in the Merelani Hills, with operations ranging from large-scale commercial mining to small-scale artisanal mining. The gems are typically found in elongated, prismatic crystals, which are then cut into various shapes for jewelry. The rarity of the source and the difficulty of mining contribute to the gemstone’s value. For those interested in the provenance of their gemstones, knowing that a Tanzanite originates from the foothills of Mount Kilimanjaro adds a layer of narrative and connection to its natural history.
Gemological Properties
Tanzanite is a member of the zoisite mineral group, with a chemical formula of Ca2Al3(SiO4)3(OH). Its most defining characteristic is its pleochroism, a property where the gemstone shows different colors when viewed from different crystal directions. Tanzanite exhibits strong trichroism, typically appearing blue, violet, and reddish-brown or gray depending on the orientation. The primary color used in jewelry is the violet-blue hue, which is often enhanced through a controlled heating process to remove the brownish overtones and stabilize the color.
In terms of hardness, Tanzanite measures between 6 and 7 on the Mohs scale of mineral hardness. This places it in the medium range of gemstone durability, making it suitable for jewelry but requiring careful handling to avoid scratches and impacts. Its relatively low hardness compared to gems like sapphire or diamond means it should be protected from hard surfaces and not worn during activities that could subject it to physical stress.
Tanzanite has a specific gravity of approximately 3.35 and a refractive index ranging from 1.691 to 1.700. It is typically transparent to translucent, with clarity being an important factor in its value. High-quality Tanzanite is eye-clean, meaning it has no visible inclusions to the naked eye. The gemstone is often cut into faceted shapes to maximize its brilliance and color play, with common cuts including oval, cushion, and pear shapes. Carat weight is another factor in valuation, with larger stones being rarer and more valuable, especially if they exhibit even color and good clarity.
The following table summarizes key gemological properties of Tanzanite based on the provided sources:
| Property | Details |
|---|---|
| Mineral Group | Zoisite (a variety of zoisite) |
| Chemical Formula | Ca2Al3(SiO4)3(OH) |
| Mohs Hardness | 6 – 7 |
| Specific Gravity | ~3.35 |
| Refractive Index | 1.691 – 1.700 |
| Pleochroism | Strong trichroism (blue, violet, reddish-brown/gray) |
| Primary Sources | Merelani Hills, Tanzania (only known source) |
| Color Enhancement | Commonly heated to stabilize color and remove brown overtones |
Symbolism and Metaphysical Beliefs
Tanzanite is rich in symbolic meaning, particularly for those born on December 28th. As a birthstone, it is associated with qualities that resonate with the personalities of individuals born on this date. One of the most prominent meanings attributed to Tanzanite is its ability to enhance spiritual awareness and facilitate deep meditation. The gem is believed to open the third eye chakra, promoting insight, intuition, and a heightened sense of awareness. This aligns with the stone’s transformative nature, symbolizing personal growth and the journey toward higher consciousness.
In the context of birthstone symbolism, Tanzanite is often linked to transformation and new beginnings. Its discovery in the modern era and its unique color-changing properties are seen as metaphors for change and adaptation. For those born in December, which is the last month of the year, Tanzanite can represent the culmination of the year’s experiences and the promise of new cycles ahead. It is also associated with emotional healing, helping to calm the mind and release negative energies, which can be particularly beneficial for the responsible and self-controlled nature of Capricorns born on December 28th.
While some sources attribute various metaphysical properties to gemstones, it is important to note that these beliefs are not scientifically proven and are part of cultural and spiritual traditions. However, for many gemstone enthusiasts, the symbolism adds a layer of personal meaning to their jewelry. Tanzanite’s association with spiritual growth and transformation makes it a popular choice for meditation and mindfulness practices. Its calming violet-blue color is also thought to promote peace and tranquility, making it a stone of serenity and emotional balance.
Care and Cleaning
Due to its medium hardness and cleavage properties, Tanzanite requires careful handling and maintenance to preserve its beauty and durability. With a Mohs hardness of 6 to 7, it is susceptible to scratches from harder materials and can be damaged by sharp blows. It is recommended to store Tanzanite jewelry separately from other pieces to avoid contact with harder gemstones or metals. When not in use, it should be kept in a soft cloth pouch or a lined jewelry box.
Cleaning Tanzanite should be done with mild soap, lukewarm water, and a soft brush. Avoid using ultrasonic cleaners, steam cleaners, or harsh chemicals, as these can damage the gemstone or affect any treatments it may have undergone. After cleaning, rinse thoroughly and dry with a soft, lint-free cloth. It is also advisable to have Tanzanite jewelry inspected regularly by a professional jeweler to check for loose settings or any signs of wear, especially if the piece is worn frequently.
For those who wear Tanzanite daily, it is best to put it on after applying cosmetics, perfumes, and hairsprays, as these substances can leave a film on the gemstone and dull its brilliance. It should also be removed before engaging in physical activities, household chores, or swimming to prevent exposure to chemicals and physical impacts. With proper care, a Tanzanite piece can remain a stunning and meaningful gemstone for a lifetime, serving as a beautiful reminder of its unique origin and the personal significance it holds for the wearer.
Conclusion
Tanzanite stands out as a remarkable gemstone for those born on December 28th, offering a unique combination of rare beauty, geological intrigue, and profound symbolism. Its discovery in the 1960s in Tanzania introduced a new and vibrant color to the world of gemstones, and its designation as a modern birthstone for December has secured its place in the hearts of many. The gem’s pleochroism, medium hardness, and single geographic source make it a fascinating subject of study and a prized possession. Whether valued for its aesthetic appeal, its association with spiritual transformation, or its status as a birthstone, Tanzanite continues to captivate and inspire. For the individual born on December 28th, wearing Tanzanite is not just a celebration of their birth month but a connection to a gemstone that embodies the essence of individuality, growth, and the enduring beauty of the natural world.