Green green food colorings which has been approved by the US Food and Drug Administration. Chlorophyll, the E numbers E140 and E141, is the most common green chemical found in nature, and only allowed in certain medicines and cosmetic materials. Quinoline Yellow (E104) is a commonly used coloring in the United Kingdom but is banned in Australia, Japan, Norway and the United States. Green S (E142) is prohibited in many countries, for it is known to cause hyperactivity, asthma, urticaria, and insomnia. To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also
Barium sulfate casting of copper anode plates. The anode plates are cast in copper molds, so to avoid the contact of the liquid copper and the solid copper mold, a solution of barium sulfate in water is used as a coating material on the mold surface. Thus when the liquid copper solidifies in form of an anode plate it can be easily released from its mold. Barium sulfate is sometimes used (or else PTFE) to coat the interior of integrating spheres due to the high reflectance of the material and near Lambertian characteristics. Almost all of the barium consumed commercially is obtained