ITEMSPECIFICATIONAssay (NAHSO4)>=99%Sodium sulfate(NA2SO4)<=0.8%ColorWhite to off-whiteIron(mg/kg)<=20PPMHeavy metals(as PB, mg/kg)<=20PPMAS(mg/kg)<=2PPMMoisture, as water<=0.5%Water-insoluble substances<=0.05%