History of magnesia

The Chemistry and Technology of Magnesia, by Mark A. Shand Copyright 2006 John Wiley Sons, Inc. 

The metal from magnesia appears to react with the glass, especially before all the mercury has distilled off. In one experiment, in which I interrupted the distillation before the mercury had been completely removed, the metal appeared 

Eventually, much to the consternation of Davy, the name magnesium was adopted for the metal in magnesia alba and manganese for the metal in pyrolusite. Michael Faraday produced magnesium metal in 1833 by the electrolysis of fused anhydrous magnesium chloride. 

An immense deposit of medium- to low-quality magnesite exists in Steven County, Washington, which was exploited by the Northwest Magnesite Company during World War I. Operations were centered on the towns of Chewelah and Valley. It was here that the first use of froth flotation to beneficiate magnesite was employed to reduce silica and lime content. 

(1777). Experiments upon Magnesia ALBA, Quick-Lime, and other Alkaline Substances. W. Creech Edinburgh. 

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HISTORY. Centuries ago, the ancient Romans claimed that magnesia alba (white magnesium salts from the district of Magnesia in Greece, from which the element was eventually named) cured many ailments. But, it was not until 1808 that Sir Humphrey Davy, the British chemist, announced that he had isolated the element, magnesium. 

A. Lavoisier included lime and magnesia into The Table of Simple Bodies but excluded potassium and sodium hydroxides believing that they had complex composition and their nature had to be further studied. One might say that history was unjust to these elements, for barium, for instance, was isolated in a metallic state simultaneously with them, but had been discovered mnch earlier. However, history is a wayward lady. The discovery of sodium, potassium, magnesium, and calcinm is interesting in that it was made possible by electric cnrrent being successfully used for the first time. This marked the birth of the electrochemical method, a subsidiary to the chemical analysis. Subsequently, electrolysis of melted compounds made it possible to obtain other metals discovered earlier in their compounds. 

HISTORY. Manganese was first recognized as an element in 1774 by the famous Swedish chemist Carl W. Scheele. It was isolated in the same year by his co-worker, Johann G. Chan. The name manganese is a corrupted form of the Latin word for a form of magnetic stone, magnesia. 

Continuously cured profiles are based on very fast curing compounds, a cure of Imin at 200 °C being typical so that thiourea acceleration is necessary, with DETU (Iphr) most commonly used. Frequently the magnesia is reduced from the standard 4 phr to 2 phr to obtain a faster onset of cure. The processing safety of these compounds is obviously limited and requires careful control of all processing steps to limit the heat history. The compounds should be two stage mixed with the accelerators added shortly before extrusion. 

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