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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THE ANTIMONY PREPARATIONS AND THEIR USES. 157<br />
dried at 100°. Again, a mixture of bauxite and antimonic acid may<br />
first be treated with steam, and then calcined slowly under a current<br />
of carbonic acid gas. Finally, the antimoniates of manganese and of<br />
zinc give a good white colour.<br />
(b) Antimony Black.—It is obtained by treating antimony<br />
solutions with zinc or iron. The deposit thus obtained is in the form<br />
of powder, and ia used to bronze metals or plaster.<br />
(c) Antimony Vermilion.—Lampadius, in 1853, proposed using<br />
the red sulphide of antimony as a pigment, which, as he observed,<br />
covers well when employed with water, but possesses less body when<br />
ground with oil.<br />
M. E. MathieurPlessy writes thus* :—"The product to which I<br />
give the name vermilion of antimony is the result of a new modification<br />
of the sulphide of antimony which I obtain from the decomposition<br />
of hyposulphite of soda in the presence of chloride of<br />
antimony.<br />
"Among the phenomena of double decomposition, so characteristic<br />
of the nature of mineral substances, none is more striking than the<br />
production of the orange-yellow sulphide of antimony by means of<br />
sulphuretted hydrogen or of an alkaline sulphide. If the latter<br />
reagent, from long exposure to the air, be partly transformed into<br />
hyposulphite, it may give with a proto-salt of antimony variously<br />
coloured precipitates, the colour depending on the degree of oxidation.<br />
These variations, which may have been already observed, will<br />
be easily explained by the reaction studied by myself, which gave the<br />
key for obtaining a red sulphide of antimony entirely distinct from<br />
the well-known ones hereafter mentioned.<br />
" I refer to the orange-yellow sulphide, produced by the reaction of<br />
sulphuretted hydrogen upon the proto-chloride of antimony, the<br />
black native sulphide, and the brown-red sulphide, a modification of<br />
the preceding one, which was observed for the first time by Fuchs,<br />
and has recently been studied by Mr Rose.<br />
" It is not sufficient, however, to put the proto-chloride of antimony<br />
and the hyposulphide of soda in contact with each other to obtain<br />
the sulphide of antimony with all the brightness which it is able to<br />
acquire. In order always to arrive at the desired result, I have been<br />
obliged to make numerous trials and to vary the proportions of the<br />
reagents and the temperature. At last I have succeeded in finding<br />
out a process which is satisfactory in regard to the quality of the<br />
product and the facility of its preparation.<br />
" Believing that the vermilion of antimony might find its applica-<br />
* Bull, de la Soc/UU industrielle de Mulhousc, vol. xxvi. pp. 297 et seq.