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Copper-bearing tourmalines from Brazil were obtained at the Tucson show in 2005 from 3 differ-ent sources specialized in “Paraiba”- tourmaline from the Batalha mine (Van Wagoner, R.C. Gemmas, Bryan Pavlik). These materials were partially from old inventories from the production year 1988 (Lit Par16). Photographs of the materi-als see Fig. Par10, 17, 29, 58 and 61. Brazilian samples from Rio Grande do Norte were obtained from P. Wild (IdarOberstein, Germany) that originated from their own mining operation (Fig.Par64 and 65).
Copper-bearing tourmalines from Mozambique were received from Gebr. Bank (Idar Oberstein) in 2006 (produced in 2005, samples 2939, 2942, 2942.2, 2943, Tab. Par05) and further materials were acquired from African suppliers in Bangkok in the years 2006 and 2007 (Fig. Par06, 67a-b, 72, 74, 75 and 77). Nigerian copper-bearing tourmalines were acquired from Arnold Silverberg, Steve Jaquith in Bangkok and from Paul Wild.
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A total number of 120 faceted or rough materials were available for this study. From these stones 90% are unheated materials. All multicolored copper-bearing tourmalines used for LA-ICP-MS analysis are unheated. No multicolored samples were available from the origin of Nigeria.
In addition, over 100 gem-quality faceted “Paraiba”-type tourmalines from Brazil and over 600 faceted counterparts from Mozambique, both heated and unheated have been tested and certified in the GRS laboratory between 2004 and 2008. These high-valued gemstones are considered representative to the size and color of copper-bearing tourmalines available in the worlds gem market and have been used for a statistical study (Fig. Par07, 08, 11 and 12).
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Materials and Statistics
