USES OF MAGNESITE
Magnesite and its derived products are used in a variety of industries, the most essential of which, beyond doubt, is metallurgy. Owing to the high fusion point and chemical inertness of the oxide of magnesium, magnesite is one of the principal minerals used in the metallurgical and other industries where highly refractory material is required. For this purpose dead-burned magnesite is used in the form of brick or of grains. Brick and shapes are employed for lining open-hearth steel furnaces, welding, heating, and melting furnaces, reverberatories, settlers, and furnaces for refining lead, copper converters, and electrical furnaces. Crushed or granular magnesite is used for lining the bottoms of open-hearth steel furnaces, and in making crucibles and cupels.
In the manufacture of the cement known as oxychloride or Sorel cement the quantity of magnesite used is exceeded only by that used for refractory purposes. This cement is employed largely for sanitary flooring, and to a less extent for wall plaster, both interior and exterior. It is used also instead of Portland cement for some forms of exterior construction where quick and strong set is required. Magnesite is used in the manufacture of wood-pulp paper on the Pacific Coast, in fire-resisting paint, as a non-conductor of heat in pipe and furnace coverings, and in the manufacture of magnesium chloride, light carbonate, and other products, including metallic magnesium.