Formula: Al2(SO4)3 . 18H2O Description: White or grayish piece, soluble in water. Specification: Al2O3 content 16-18% Analysis: As2O3 0.01%max Fe2O3 0.35%max Free acid none Water insolubles 0.1%max Size 1-10cm Uses: Used for the manufacturing of wood 杙ulp,paper,alum,aluminium salt, printing ink,lubricant,boiler cleaning agent,satin white,oilcloth,linoleum,ceramics,for sizing paper,clarifying fats and oils,tanning white leather,and water purification as deodorization and decolourizer in petroleum refining,as filtering medium water-proofing agent,and as mordant in dyeing.