“ Barite, or barytes as it is called commercially, is used as a substitute for or an adulterant of white lead in the manufacture of white pigments; for this purpose it must be free from iron, and therefore its preparation for market consists not only in grinding, but in some cases may include treatment with sulphuric acid to remove the stains. The main supply of barite is obtained from Missouri, North Carolina, Virginia, and Tennessee. It is cheaper than white lead, and does not turn yellow on exposure to the air. ”

“ Metallic paint is a term applied to certain materials obtained by the grinding of hematite ores. The color of the paint is often changed or improved by previous roasting; the iron ore most frequently employed is that known as the Clinton ore, occurring in the Clinton division of the Silurian system of rocks. ”

“ Metallic paint is mined in several States, notably New York, Pennsylvania, Wisconsin, and Tennessee; it is frequently employed for coloring mortars. Graphite and graphitic shale are used for making black paint, and have been found specially desirable for the coating of metallic surfaces. ”