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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