gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1998.62A.2.314 The Precise Measurement of Thallium Isotopic Compositions by MC-ICPMS: Application to the Analysis of Geological Materials and Meteorites Rehkämper M. Halliday A. N. Department of Geological Sciences, The University of Michigan, Ann Arbor, MI 48109-1063, USA 1998 62A 2 1241 1242 Copyright © 1998, The Mineralogical Society 1998