AM_Krausite
Formula: Fe K S2 O9 H2
Name: Krausite
Unit cell: 7.908 5.152 8.988 90.0 102.75 90.0 , V=357.16
Space group: P121/M1 (11)

Graeber E J , Morosin B , Rosenzweig A , American Mineralogist , 50 (1965) p.1929-1936, The crystal structure of krausite, KFe(SO4)2.H2O