gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1991.055.378.01 Geothermometry and Geobarometry—Introduction Yardley B. W. D. Department of Earth Sciences, University of Leeds, Leeds LS2 9JT, U.K. Schumacher J. C. Mineralogisch-Petrographisches Institut der Universität Kiel, Olshausenstrasse 40, D-2300 Kiel, Germany 3 1991 55 378 1 2 15 10 1990 Copyright © 1991, The Mineralogical Society 1991