Blue topaz has emerged as a popular and widely recognized birthstone for December, with London blue topaz representing its darkest and most sought-after variety. This gemstone, prized for its rich, inky hue and versatility, holds a fascinating place in both gemological history and contemporary jewelry design. This article will explore the origins, properties, symbolism, and care of London blue topaz, drawing upon current understanding of this captivating gem.
History and Lore
The name “topaz” itself originates from the Sanskrit word “tapas,” meaning fire, a reference to the gem’s inherent brilliance. While the history of topaz extends back centuries, with ancient Egyptians and Romans valuing it for its perceived protective and healing qualities, the prominence of blue topaz is a more recent development. Blue topaz gained significant popularity during the Victorian era, becoming a favored gemstone for jewelry creations.
Traditionally, December boasted other birthstones, including turquoise, lapis lazuli, and tanzanite. However, in modern times, blue topaz, alongside blue zircon and tanzanite, has become a dominant choice for those born in the twelfth month. The name “London blue topaz” specifically arose from the presence of a massive 9,381-carat blue topaz displayed in the UK Natural History Museum, establishing a connection between the gem and the city.
Geological Formation and Sources
Blue topaz belongs to the silicate family, with a chemical composition of Al2Si04(F,OH)2, or Aluminum Fluoro-Hydroxyl-Silicate. It crystallizes within the orthorhombic crystal system and registers an 8 on the Mohs hardness scale, indicating a relatively durable gemstone. While naturally occurring blue topaz exists, it is quite rare. The vast majority of blue topaz available commercially is produced by irradiating naturally colorless topaz, a process that enhances its color.
The primary sources of topaz, and subsequently the material used to create blue topaz, include Brazil, Russia (specifically the Ural Mountains), Pakistan, Zimbabwe, and even Mason County, Texas, which designates blue topaz as its official state gem. However, Brazil currently stands as the leading source for the majority of blue topaz found in the market.
Gemological Properties
Blue topaz exhibits a glass-like luster and ranges in color from very pale to dark, inky blue. London blue topaz, in particular, is characterized by its deep, saturated blue hue, often with a subtle greenish tinge resulting from heat treatment processes used to stabilize the color. This variety is distinguished by its darker tone and saturation compared to other blue topaz shades like Swiss blue (a vibrant, medium light blue) and sky blue (a light aqua color).
The gem’s chemical bonding is strong, contributing to its hardness, though it is also somewhat brittle and possesses perfect cleavage, making it susceptible to scratches and impacts. Its chemical formula is Al2SiO4(F,OH)4. London blue topaz typically commands higher prices, ranging from 10-30 US dollars per carat, reflecting its desirability and relative scarcity within the blue topaz spectrum. The cut of the stone significantly impacts its value, often contributing as much as the color itself.
Here's a table summarizing key gemological properties:
| Property | Description |
|---|---|
| Chemical Formula | Al2Si04(F,OH)2 / Al2SiO4(F,OH)4 |
| Crystal System | Orthorhombic |
| Hardness (Mohs) | 8 |
| Luster | Glass-like |
| Cleavage | Perfect |
| Color | Pale to dark inky blue |
| Specific Gravity | Not specified in sources |
| Refractive Index | Not specified in sources |
Symbolism and Metaphysical Beliefs
Blue topaz is often referred to as the “clarity stone,” believed to stimulate open communication and encourage positive action. It symbolizes opportunity and possibility, and is thought to promote wisdom, emotional honesty, and reduce stress. Some believe that wearing blue topaz near the neck supports throat health.
Beyond these general associations, the gem has been historically valued for its perceived protective and healing properties. While these beliefs are not scientifically substantiated, they contribute to the gemstone’s enduring appeal and cultural significance.
Care and Cleaning
Despite its hardness, blue topaz is somewhat brittle due to its perfect cleavage. Therefore, it should be handled with care, especially when set in jewelry prone to impacts. To maintain its brilliance, blue topaz jewelry should be cleaned regularly with warm, soapy water and a soft brush. Avoid harsh chemicals, ultrasonic cleaners, and steam cleaners, as these can damage the stone. It is also advisable to store blue topaz jewelry separately from harder gemstones to prevent scratching.
Distinguishing Blue Topaz from Similar Gems
It is important to note that natural blue topaz can sometimes be mistaken for aquamarine due to similar color profiles. Additionally, blue topaz is often compared to blue zircon and tanzanite, both of which are also recognized as December birthstones. However, zircon boasts a higher refractive index and exceptional brilliance, while tanzanite exhibits a unique color-shifting quality between blue and purple (pleochroism). Blue topaz, particularly London blue, is generally more affordable than both zircon and tanzanite.
The Appeal of London Blue Topaz
London blue topaz stands out as a particularly attractive option for those seeking a December birthstone. Its deep, inky blue color offers a sophisticated and versatile aesthetic, suitable for both casual and formal wear. Its relative affordability and availability in various shapes and sizes further contribute to its popularity among jewelers, designers, and consumers alike. The gem’s association with clarity, communication, and positive energy adds another layer of appeal, making it a meaningful and beautiful choice for those born in December.
Conclusion
London blue topaz has firmly established itself as a prominent and beloved December birthstone. Its captivating color, combined with its historical significance, symbolic meaning, and relative accessibility, makes it a compelling choice for jewelry enthusiasts and those seeking a meaningful gemstone. While most commercially available blue topaz undergoes irradiation to achieve its vibrant hue, the resulting gem remains a testament to the beauty and enduring allure of the natural world. Its durability, though requiring careful handling, ensures that London blue topaz can be cherished for generations to come.