Antimony, Bismuth, and Cobalt.

Scientific American 26, 7.5.1857

In a lecture recently delivered before the Royal School of Mines, England, on the property of these metals, the lecturer (Dr. Percy) remarked as follows: -

When copper was mixed with antimony in excess, it formed a regulus of beautiful violet color, which by the old alchemists was denominated regulus of Venus. Antimony entered largely into the composition of type metal; a good mixture for this is three parts of lead and one antimony, and sometimes a small quantity of tin is added. He did not believe there was any specific standard for type metal, as, in many cases, the several founders had each a formula of their own. When antimony was alloyed with copper it was found brittle; the specific gravity of this alloy was greater than the mean of the two metals. It had been proved that antimony had been used in the composition of bells, and a work was publsihed in Madrid, in 1567, which stated that several bells in Spain contaned that metal. The Chinese had likewise used antimony for the purpose of making mirrors. This composition consisted of copper, 80,33, lead 9,71, antimony, 8,48, and of iron a mere trace.

A patent metal had been invented by Mr. Wetterstedt, for the purpose of sheating ships. He had not heard much of this, and therefore, presumed its application had not been so successful as had been anticipated. This metal was composed of antimony, 4,3, lead, 4,4, mercury 1,3.

Bismuth had been known for the last three hundred years. At first it was mistaken for lead, and as such often used in cupellation. Its ore occurs with several other metals, more especially cobalt.

Commercial bismuth was never pure, and sometimes it contained as much as sixty ozs. of silver to the tun, and this he wished to be publicly known. According to Schorer, the specific gravity of the cure metal was 9.783, while that of the pure metal was 9,779. Its melting point was 264°. It did not sensibly oxydize when exposed to moisture.

Berthier had stated that an alloy of 66 parts of lead and 34 parts of bismuth was more tenscious than lead, possessing a color between tin-white and lead-grey. This could be beaten out into thin foil, and was fusible at 166°. Bismuth could be mixed with mercury witout the latter losing its fluidity. Lead and bismuth were often used for the purpose of adulterating mercury, and bismuth was likewise employed for the purpose of silvering glass.

Cobalt had been used as a coloring matter in ancient times; but the blue glass and the enamels the British Museum which he had examined, had received their colors from copper, not cobalt. In Saxony and Norway, where there are large establishments for the reduction fo cobalt, the operations are carried on with great secrecy.

Cobalt sold some years since for £2 2s. per pound, and now only realised 18s. The mode of separating cobalt from nickel could be found in Gmelin's Handbook of Chemistry, and other works. The oxyd of cobalt had been found in Missouri, accompanied with oxyd of manganese. The introduction of artificial ultramarine had greatly lessened the price, it now being used in several instances in lieu of cobalt.

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