Solution-Generated Pink Colour Surrounding Growth Tubes and Cracks in Blue to Blue-Green Copper-Bearing Tourmalines from Mozambique
Several transparent, faceted, blue to blue-green copper-bearing tourmalines containing growth tubes and cracks surrounded by sleeves of pink colour were examined for this report.
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.
Copper and tenorite inclusions in cuprian-elbaite tourmaline from Paraíba, Brazil
Inclusions of native copper and tenorite (CuO) were found in greyish-green elbaite from São José da Batalha, Paraíba, Brazil.
An Update on “Paraíba” Tourmaline from Brazil
“Paraíba” tourmalines continue to be recovered in small amounts from north-eastern Brazil.
Gem pegmatites of Minas Gerais, Brazil: the tourmalines of the Araçuaí districts
This second article in the series on Minas Gerais describes the major tourmaline deposits which produce some of the finest specimens ever seen.
The Elahera Gem Field in Central Sri Lanka
The Elahera gem field currently provides approximately 35% of the gemstones exported from Sri Lanka.
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.
Interesting Red Tourmaline from Zambia
A new source of red tourmaline is identified in Zambia.
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.