Lithopone was discovered in the 1870s by DuPont. It was manufactured by Krebs Pigments and Chemical Company and other companies. The material came in different seals, which varied in the content of zinc sulfide. Gold seal and Bronze seals contain 40-50% zinc sulfide, offering more hiding power and strength. Although its popularity peaked around 1920, approximately 223,352 tons were produced in 1990. It is mainly used in paints, putty, and in plastics.
1. Purity The purity of barium sulphate is essential, especially in applications such as pharmaceuticals. Suppliers should provide certifications stating the purity levels and any presence of impurities or contaminants.