AM_(H3O)Fe(SO4)2 Formula: Fe S2 O9 Name: (H3O)Fe(SO4)2 Unit cell: 4.801 8.271 8.311 70.605 89.959 89.951 , V=311.29 Space group: P-1 (2)

Peterson R C , Valyashko E , Wang R , The Canadian Mineralogist , 47 (2009) p.625-634, The atomic structure of (H3O)Fe3+(SO4)2 and rhomboclase, (H5O2)Fe3+(SO4)2*2H2O, Locality: synthetic