CIBJO Blue Book Defines Paraíba

In the 2006/07 edition of the CIBJO Blue Books (Annex B – Commercial Names), the name Paraíba stands for any green-to-blue tourmaline colored by copper, regardless of country of origin. The standards found in the Blue Books are established by experts on the subject within CIBJO committees, and from individuals outside the committees who express interest in developing the guidelines.

Roland Naftule, Nafco Gems Ltd., Scottsdale, Ariz., president of CIBJO’s Sector 3 (Gem Materials, Trade and Laboratories), confirms that Paraíba has been designated a color variety of elbaite tourmaline containing copper and manganese. “CIBJO is the only official international body that regularly votes and assigns gemstone variety names,” Naftule explains. Both CIBJO and the Laboratory Manual Harmonization Committee define Paraíba tourmaline as a trade name that refers to color and composition without regard to geographic origin.

Copper-bearing elbaite tourmalines are found in Brazil (Paraíba and Rio Grande del Norte) and Africa (Nigeria and Mozambique). All the deposits have colors ranging from purple to green.

The color is related to rare trace elements of copper and manganese. Country-of-origin determination of most Paraíbas is possible, but only with sophisticated instrumentation. “It is based on elements such as beryllium, lead, bismuth, gallium, and zinc,” says Dr. Michael Krzemnicki, deputy director of SSEF Swiss Gemmological Institute, Basel, Switzerland. “Origin determination based on traditional gemological testing or color is not conclusive. While there is still some controversy about the terminology, these stones will find their public due to their beauty.”

Some exhibitors at the recent gem shows in Tucson, Ariz., weren’t shy about stretching the new definition of Paraíba.

Paraíba seems to be freely used by some at Tucson to describe anything of a bright bluey color,” says Dr. Jack Ogden, chief executive of the Gemmological Association of Great Britain. “The blue quartz I saw ranged from bright topaz blue to a darker more tanzanite color.” The color is said to be created by heat treatment plus irradiation.

Some other “Paraíba” quartz seen in Tucson was actually rock crystal filled with a blue copper mineral called Gilalite (pronounced HEE-luh-lite).