A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...
A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...
A N T I M O N Y : ITS HISTORY, CHEMISTRY, MINERALOGY ...
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CHAPTER V.*<br />
THE METALLUBGY OF ANTIMONY.<br />
THE principal ore for the extraction of antimony is sulphide of<br />
antimony or stibnite, commonly known as antimony-glance. The<br />
other ores—cervantite or antimony-ochre, kermesite, valentinite,<br />
senarmontite, which occur only in small quantities in nature—<br />
together with the fumes and slags from the previous smelting of<br />
antimony, are generally mixed up with antimony-glance preparatory<br />
to smelting. Dry methods are generally adopted for the extraction<br />
of the metal, or of the metal in different combinations, while<br />
the proposals for the use of wet processes or of electro-metallurgical<br />
methods have not yet found practical application. The more or<br />
less pure sulphide of antimony is called ''crude antimony," and the<br />
refined metal itself is called "antimony regulus."<br />
I. EXTRACTION BY DRY METHODS.<br />
A. Preparation of Products for the Extraction of Metallic<br />
Antimoiiy.<br />
1. Liquation of Crude Antimony.—Ores containing more than 90<br />
per cent, of the sulphide do not require any further treatment, and<br />
are considered to be crude antimony. Ores containing less than 90<br />
per cent, and more than 40 or 50 per cent, are subjected to the<br />
liquation process for the production of crude antimony. The best<br />
size of the pieces of ore for this treatment is walnut size. Smallersized<br />
ore or ores of poorer quality are generally worked up for the<br />
production of the metal.<br />
The maintenance of the proper temperature in the liquation process<br />
is very important, in order to obtain the best result. If the temperature<br />
is above a red heat the sulphide is volatilised, and if the tem-<br />
* In the compilation of this chapter, use has been made of the information<br />
contained in the standard metallurgical works of Phillips and Bauerman, of Bruno<br />
Kerl, and of Carl Schnabel in drawing up the descriptions of the older methods.<br />
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