Fluorapophyllite_3 Formula: F K Ca4 Si8 O26.88 H13.76 Name: Fluorapophyllite Unit cell: 8.9639 8.9639 15.754 90.0 90.0 90.0 , V=1265.86 Space group: P4/MNC (128)
Stahl K , European Journal of Mineralogy , 5 (1993) p.845-849, A neutron powder diffraction study of partially dehydrated, fluorapophyllite, KCa4Si8O20F*6.9H2O