gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1959.32.245.04 A Mineralogical Application of X-ray Absorption Microspectroscopy: The Hydration of Larnite Long J. V. P. M.A. Cavendish Laboratory McConnell J. D. C. M.Sc., M.A., Ph.D. Dept. of Mineralogy and Petrology University of Cambridge 7 1959 32 245 117 127 Copyright © 1959, The Mineralogical Society 1959 Summary

The technique of X-ray absorption microspectroscopy is described, with particular reference to the determination of calcium in a hydrogel formed in minute amounts in cavities in larnite. The method, which is applicable to other elements, enables chemical data to be obtained from selected small areas in a normal petrological thin section.