The Mineral Industry Volume 22 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1914 Excerpt: ...wider use in this country. It is also reported to have found a use in the manufacture of artificial marble and fine tiles. Other Uses.--Magnesite in both crude and calcined form finds numerous miscellaneous applications, among which may be mentioned its use as heat-insulating pipe covering. For this purpose it is commonly mixed with asbestos fiber, and the artificial magnesia alba levis seems to be best. Magnesite is said to be used as an anti-acid in the manufacture of dynamite, as an adulterant in paint, and as a preventive of scale in boilers in which sulphurous waters are used. It has been tried with some success as a binder for briquetting coal, where it has the disadvantage common to all inorganic binding materials, namely, that they increase the ash without adding to the combustible portion of the fuel. The use of magnesite in a fireproof or fire-retarding paint is also reported to be increasing. Wood and burlap coated with a paint made of magnesite are said to resist fire so that, while they can be burned by the direct application of heat and flame, the fire will not spread beyond the area actually exposed to the flame. Refined magnesia salts are used for medicinal and toilet purposes. The commercial preparation known as magnesia alba is a basic carbonate of slightly varying composition, according to the conditions of production. It is usually prepared by precipitation of either the commercial sulphate or chloride of magnesium with sodium carbonate. Epsom salts (magnesium sulphate) is derived from the deposits at Stassfurt, Germany, and is imported on a considerable scale but is also manufactured by the chemical treatment of magnesite. A considerable quantity of magnesia quoted as "medical, calcined" is imported annually, probably represen...