ANALYSIS OP ORES OF ANTIMONY.

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Experiment VIII.

Preparation of cinnal-ar of antimony.

Pulverize one part of sulphuret of antimony and three of oxi-genated muriate of mercury, according to Baume ; but accord-ing to Fourcroy, one part of the former to two of the latter, mixthese substances and proceed in other respects as in the preced-ing operation. When the distillation is finished, adapt ano-ther receiver to the retort and sublime the residuum with astrong heat. A substance will be obtained in the form of redneedles called cinnabar of antimony.

This is the effect of a double affinity. The sulphuret of anti-mony exchanges its sulphur for the acid given up by the oxige-nated muriate of mercury.

The combination of antimony with other metals is not attend-ed with any difficulty.

ANALYSIS OF ORES OF ANTIMONY.

These ores may be analyzed by digesting by heat one part ofthe ore, reduced to a fine powder, in four parts of nitro-mu-riatic acid, composed of three or four of muriatic acid, andone of nitric acid. The sulphur contained in the ore will re-main behind untouched. On filtering the solution, the antimonymust be disengaged by the mere admixture of water, and maybe collected on a filter. To reduce it to the metallic state let itbe mixed with double its weight of charcoal and fuse it in a cru-cible. The metal will then be found at the bottom.

As lead and iron are sometimes present in these ores theymay be detected by letting fall into the last solution from whichthe antimony has been separated, a few drops of sulphuric acid jif lead be present a white precipitate will ensue. If iron be pre-sent a yellowish-brown precipitate will take place on addingliquid ammonia to the solution.

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