Barium Sulphate exists as white powder at room temperature. It is water soluble salt. White Pigment for paints. filler in plastics and as a component of oil well drilling fluid to increase the density. Powder coatings. Frequently used clinically as a radiocontrast agent for X-ray imaging and other diagnostic procedures. (Barium meal). Putty grade blanc fixe is used as a filler in Epoxy Putty manufacturers.