Yellow, manganese rich elbaite with manganese-titanium intervalence charge transfer

George R. Rossman and Stephanie M. Mattson
Division of Geological and Planetary Sciences
California Institute of Technology, Pasadena, CA  91125, USA


The color of yellow-green to yellow-brown Mn-rich elbaite tourmalines from Zambia and Nepal is controlled by Fe2+ - Ti4+ (brown) and Mn2+ - Ti4+ (yellow-green) intervalence charge transfer. The proposed Mn-Ti interaction resposible for an absorption band centered at 325 nm is especially well developed in the Zambian tourmaline whos spectroscopic properties are discussed.