... paint, kaolin, magnesium oxide, calcium carbonate drilling mud, preservative agent for paper making, organic synthesis catalyzer, and used in epuration of ... % water solution: 9.5-10.0 Chloride, as cl: 0.025% max Heavy metals, as Pb: 0.001% max Pb: 0.0001% max Arsenic, as ... As: 0.0001% max Fluoride as F: 0.003% max Water insoluble ...