AM_Protoferro-anthophyllite Formula: Fe6.5 Mg.1 Mn.4 Si8 O24 H2 Name: Protoferro-anthophyllite Unit cell: 9.388 18.387 5.347 90.0 90.0 90.0 , V=922.98 Space group: PNMN (58)

Sueno S , Matsuura S , Gibbs G V , Boisen M B , Physics and Chemistry of Minerals , 25 (1998) p.366-377, A crystal chemical study of protoanthophyllite:, orthoamphiboles with the protoamphibole structure, Sample: PFA Hiruka Village