Spectral Differentiation Between Copper and Iron Colourants in Gem Tourmalines
The authors used Vis-NIR spectral measurements combined with LA-ICP-MS data to investigate the usefulness of absorption spectra.
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.
Abstracts; Summer 1991
From the Summer 1991 issue of Gems & Gemmology, a summary of important gemmology-related articles published in other journals.
Trapiche Tourmaline from Zambia
Green tourmaline from north-western Zambia show a growth pattern reminiscent of trapiche emerald/ruby when sliced perpendicular to the c-axis.
Cuprian Liddicoatite Tourmaline
Identifies 13 copper-bearing tourmalines, which have traditionally been assumed to be elbaite species, as liddicoatite.
Summer 2009 G&G Lab Notes
This section, from the Summer 2009 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.
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.
Multicoloured Bismuth-bearing Tourmaline from Lundazi, Zambia
Tourmalines from an alluvial deposit near Lundazi in Zambia consist of colour-zoned pink/colourless/yellow-green “watermelon” nodules.
Gemstone Durability: Design to Display
A treatise on the design, display, care and repair of fine gemstones.
Gem-Bearing Pegmatites: A Review
A survey of the current gemmological knowledge of pegmatites, including the gem varieties aquamarine, tourmaline and topaz.