Friday, 22 June 2012


It is a rare event when a new gem variety causes tremendous excitement in the gemstone world. It happened with tanzanite in the 1960's, but only with the marketing muscle of Tiffany & Co. behind it. The case of paraiba tourmaline in the 1990's was a different story.
The unusual blue-green paraiba tourmaline was first discovered in the Brazililan state of Paraiba in 1989 by a dedicated miner named Heitor Barbosa. Barbosa worked the Mina da Bathalha for over 5 years before he found the first samples of this extremely rare tourmaline. These gems had an unusual vivid blue-green that had never been seen before in any gemstone. They appeared to glow with a neon or electric-like quality, even in the rough stone. Analysis showed that this unique effect was due to the presence of copper and manganese.
The paraiba tourmaline was first introduced to the gemstone world at the annual Tucson gem show in early 1990. It caused an immediate sensation. Top specimens sold for as much as $3,000 a carat. At the time that price seemed ridiculously high for a tourmaline; today, ironically, it seems ridiculously low.

The market demand for the paraiba tourmaline was so strong, and the supply so limited, that it became nearly impossible for gem dealers to buy stock. However, in 2001 some similar copper-bearing blue-green tourmaline was discovered in Nigeria, though the color saturation was not as good as the Brazilian material. Then in 2005 a third find was made, this time in Mozambique. The Mozambique material is found in a range of colors, from green to blue-green to violet, with color more similar to the Brazilian paraiba. In fact the Mozambique paraiba is often cleaner than the Brazilian (which tends to be heavily included) and is found in larger sizes.

The new finds of copper-bearing tourmaline led to a vigorous debate in the gemstone community about whether the term "paraiba" should be used for the African copper-bearing tourmaline. Some argued that the Brazilian and African material were chemically similar, if not identical. Others argued that "paraiba" was a location name and should be reserved for the Brazilian material only. Some gem dealers started to use the term "African paraiba."
In 2006, the LMHC (Laboratory Manual Harmonization Committee) agreed that "paraiba" should refer to a species of tourmaline, and not indicate a geographic origin. The term "paraiba" should not be capitalized (as it is in the name of the Brazilian state). The term "paraiba tourmaline" may now refer to gems found in Brazil, Nigeria, and Mozambique, and wherever new deposits of copper-bearing tourmaline may be found in the future.

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