AM_Wightmanite Formula: Mg5 B O10.4 H13 Name: Wightmanite Unit cell: 13.46 3.1 18.17 90.0 91.6 90.0 , V=757.87 Space group: I12/M1 (12)

Moore P B , Araki T , Nature Physical Science , 236 (1972) p.25-26, Wightmanite, Mg5(O)(OH)5(BO3)*nH2O, a natural drainpipe, Locality: Crestmore, California, USA