Aluminium potassium sulphate/Posash Alum 1,GB1895-94 2,Purity:99.2% min 3, prompt shipment 4,water treatment Aluminium potassium sulphate/Posash AlumGeneral information ... ,Molecular weight : 474.37 SPECIFICATION:APPEARANCE WHITE CRYSTALS OR POWDERCONTENT 99.2% MIN (ON DRY BASIS)FE 0.02% MAXPB 0 ... place away from incompatible materials. Wash thoroughly after handling. Posash Alum Lumps