gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1994.58A.1.213 The Structure of Ti-Silicate Glasses by Raman Spectroscopy: Implications for the Role of Ti in Natural Melts Henderson G. S. Department of Geology, University of Toronto, Toronto, Ontario, Canada, M5S 3B1 Fleet M. E. Department of Earth Sciences, University of Western Ontario, London, Ontario, Canada, N6A 5B7 8 1994 58A 1 408 409 Copyright © 1994, The Mineralogical Society 1994 Summary

Raman spectra of TiO2-SiO2, TiO2-Na2SiO3, TiO2-CaSiO3, and Ba2TiSi2O8 glasses have been obtained. No evidence is observed for the presence of Ti[6] in the glasses except when cryptocrystalline anatase is formed. Comparison of the glass spectra with crystalline phases with differing Ti coordination suggests that the alkali and alkaline-earth glasses contain both Ti[4] and Ti[5] with a higher proportion of Ti[4] occurring in the alkaline-earth compositions.