Chemical Specifications Appearance Fine, white, odorless, tasteless, bulky powder, free from grittiness Assay Min 97% Soluble barium compounds Max 0.005% Chloride (Cl) Max 0.05% Sulphide (S) Max 0.05 µg/g Arsenic (As) Max 0.0005% Heavy metal (as Pb) Max 0.001% Loss on ignition Max 2%