December is unique among the months, boasting not one, but two recognized birthstones: Tanzanite and Blue Topaz. While both offer striking beauty and symbolic significance, they differ considerably in origin, rarity, and value. This article will delve into the characteristics of each gemstone, exploring their history, geological formation, gemological properties, and the reasons behind their association with the final month of the year.
A History of December’s Dual Designation
The tradition of associating specific gemstones with birth months has ancient roots, tracing back to Babylonian civilizations, and later adopted by the Greeks and Hindus. These cultures believed gemstones possessed mystical healing powers and carried special meanings. However, the standardization of birthstone lists is a relatively recent development, popularized by Tiffany & Co. in 1870. Historically, multiple gemstones were often associated with a single month, allowing for choice based on personal preference or availability. This explains the dual designation for December, with Turquoise also historically linked to the month, though Tanzanite has become increasingly prominent.
Tanzanite: A Recent Discovery with Rapid Recognition
Tanzanite is a relatively recent addition to the world of gemstones, first discovered in the Merelani Hills of northern Tanzania in 1967. The gemstone’s introduction to the market occurred in 1968, thanks to Tiffany & Co., who recognized its potential and aptly named it after its country of origin. This naming convention was a deliberate marketing strategy, associating the stone with a sense of exotic allure and geographical uniqueness. Even today, Tanzania remains the only source of Tanzanite on Earth, contributing significantly to its value and exclusivity.
Geological Formation and Sources of Tanzanite
Tanzanite is a transparent variety of the mineral zoisite. Its distinctive blue or violet color is achieved through heat treatment, a common practice in the gem industry to enhance its appearance. The geological processes that created Tanzanite are complex, involving significant tectonic activity and metamorphic processes within the Merelani Hills. The specific conditions required for its formation are exceptionally rare, further explaining its limited geographical occurrence. The discovery of a 703.4-carat Tanzanite sculpture, named L’Heure Bleu (“blue hour” in French), in March 2024 by artist and jeweler Naomi Sarna, highlights the potential for exceptionally large and valuable specimens.
Gemological Properties of Tanzanite
Tanzanite is prized for its pleochroism, the ability to display different colors depending on the viewing angle. It typically exhibits violetish-blue to bluish-violet hues. The depth of color saturation is a key factor in determining its value, with more intensely colored stones commanding higher prices. Smaller Tanzanites tend to be less saturated in color, while those weighing over five carats are generally more vibrant. The quality of the cut is also crucial, as it directly impacts how the gemstone reflects and displays its colors. Tanzanite’s value is highest when it exhibits more blue than violet tones. Specific gemological data, such as refractive index and hardness, are not provided in the available sources.
Blue Topaz: A Long-Held December Favorite
Blue Topaz, alongside Tanzanite, represents December’s birthstone. Unlike the recent discovery of Tanzanite, Topaz has a long and storied history, with various colors – including blue, yellow, pink, and clear – being known and utilized for centuries. The blue variety, specifically, is often achieved through irradiation and heat treatment, enhancing its color.
Geological Formation and Sources of Blue Topaz
The sources for Topaz are more widespread than those for Tanzanite. While the provided sources do not detail specific mining locations, Topaz is found in various geological environments around the world. The process of creating Blue Topaz involves altering the natural color of the stone through irradiation, a process that introduces color centers within the crystal structure.
Gemological Properties of Blue Topaz
The sources indicate that Topaz represents love, affection, and strength. Specific gemological properties, such as chemical composition, hardness, and refractive index, are not detailed in the provided materials. The value of Blue Topaz is significantly lower than that of Tanzanite, falling within the $100-$400 per carat range.
Symbolism and Metaphysical Beliefs
Both Tanzanite and Blue Topaz are believed to carry symbolic meaning. Garnet, January’s birthstone, is associated with protection and vitality, while Emerald, May’s birthstone, symbolizes love and rebirth. While the sources do not explicitly detail the symbolism of Tanzanite and Blue Topaz beyond general associations with December, birthstones are often gifted to mark significant life events, imbuing them with personal meaning.
Value Comparison: Tanzanite vs. Blue Topaz
The most striking difference between Tanzanite and Blue Topaz lies in their value. Tanzanite commands a price of up to $1,500 per carat, while Blue Topaz is considerably more affordable, ranging from $100 to $400 per carat. This price disparity is primarily due to Tanzanite’s rarity, limited source, and the marketing efforts of Tiffany & Co. which established it as a desirable and exclusive gemstone. The provided price chart ranks Tanzanite as one of the more expensive birthstones, while Blue Topaz falls into the more affordable category.
Birthstone Price Chart Summary
The following table summarizes the price per carat for various birthstones, as provided in the sources:
| Birthstone | Price per carat | Birth Month |
|---|---|---|
| Diamond | $3000-$11000 | April |
| Ruby | $3000-$10000 | July |
| Emerald | $3000-$7000 | May |
| Sapphire | $1000-$3500 | September |
| Alexandrite | $2500-$3000 | June |
| Aquamarine | $800-$1000 | March |
| Peridot | $400-$650 | August |
| Garnet | $500-$600 | January |
| Blue Topaz | $100-$400 | December |
| Tourmaline | $100-$400 | October |
| Amethyst | $50-$90 | February |
| Citrine | $10-$50 | November |
Rarity Ranking
The sources identify Diamond, Ruby, and Emerald as the rarest birthstones. Tanzanite and Alexandrite are also noted for their rarity. Blue Topaz, while beautiful, is not considered among the rarest gemstones.
Conclusion
December’s birthstones, Tanzanite and Blue Topaz, offer a compelling contrast in terms of origin, value, and market positioning. Tanzanite, a recent discovery from Tanzania, has quickly established itself as a highly sought-after gemstone due to its rarity and captivating color. Blue Topaz, with its long history and wider availability, provides a more affordable and accessible option for those seeking a December birthstone. Both gemstones hold symbolic significance and offer a beautiful way to commemorate a December birthday or celebrate a special occasion.