gsminmag Clay Minerals Clay Minerals 0009-8558 Mineralogical Society 10.1180/minmag.1953.030.222.02 The Unit Cell and Space-Group of Chlor-Spodiosite (Ca₂PO₄Cl) Mackay A. L. M.A., Ph.D. Birkbeck College Research Laboratory, University of London. 9 1953 30 222 166 168 Copyright © 1953, The Mineralogical Society 1953