Yellow
Dravite from Tanzania
George R. Rossman, Chi Ma
Division of Geological and Planetary Sciences
California Institute of Technology, Pasadena, CA 91125
Brendan M. Laurs
Gem-A
Encinitas,
CA 92024 USA
Abstract
Yellow tourmaline from the Landanai region of Tanzania was
characterized. Its color arises from Fe
2+–Ti
4+
intervalence charge transfer. Both elements are observed in the
SEM-EDS spectrum,
A faceted dravite from Tanzania, sample GRR-3265
The optical spectrum normalized to 10 mm thickess. Data files:
E perp c;
E parallel c
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