AM_Pumpellyite-(Mg) Formula: Si3 Al2.272 Fe.358 Mg.373 Ca2 O14 H4 Name: Pumpellyite-(Mg) Unit cell: 8.8192 5.9192 19.1274 90.0 97.446 90.0 , V=990.08 Space group: A12/M1 (12)

Artioli G , Geiger C A , Physics and Chemistry of Minerals , 20 (1994) p.443-453, The crystal chemistry of pumpellyite: An X-ray Rietveld, refinement and 57Fe Mossbauer study, Note: sample K1, Locality: Keweenawan, Michigan