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Tourmaline
Tourmalines have a variety of exciting colors with one of the widest color ranges of any gem.
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Summer 2012 Gem News International
Spectral Differentiation Between Copper and Iron Colorants in Gem Tourmalines
The authors used Vis-NIR spectral measurements combined with LA-ICP-MS data to investigate the usefulness of absorption spectra.
Copper-Bearing (Paraíba-Type) Tourmaline from Mozambique
Copper-bearing tourmaline from Mozambique was first recovered in 2001, but its Cu content was not recognized until 2003, and it was not widely sold with its Mozambique origin disclosed until 2005.
Mt. Mica: A Renaissance in Maine’s Gem Tourmaline Production
The Mt. Mica area in southwestern Maine has been mined for tourmaline and other pegmatite gems since the 1820s.
An Update on “Paraíba” Tourmaline from Brazil
Vivid blue, green, and purple-to-violet cuprian elbaites, renowned in the gem trade as “Paraíba” tourmalines, continue to be recovered in small amounts from northeastern Brazil.
Copper and Tenorite Inclusions in Cuprian-Elbaite Tourmaline from Paraíba, Brazil
Inclusions of native copper and tenorite (CuO) were found in grayish green elbaite from São José da Batalha, Paraíba, Brazil.
Gem-Quality Cuprian-Elbaite Tourmalines from São José Da Batalha, Paraíba, Brazil
Unusually vivid tourmalines from the state of Paraiba, in north eastern Brazil, have attracted great interest since they first appeared on the international gem market in 1989.
A Status Report on Gemstones from Afghanistan
An overview of the plentiful and various gem materials being discovered and produced in Afghanistan.
Sri Lanka: The Gem Island
An overview of the many types of gem-quality material, and its inclusions, currently found in Sri Lanka.
Geographic Origin Determination of Paraíba Tourmaline
Copper-bearing gem tourmaline, known as Paraíba tourmaline after the location of its original discovery, is prized for its vivid blue to green color. This article explains GIA’s use of quantitative chemical analyses to distinguish samples from Brazil, Nigeria, and Mozambique.
An Update on Tourmaline from Luc Yen, Vietnam
Reviews the characteristics of tourmaline from pegmatites in the Luc Yen district of northern Vietnam.
