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The sulphurated silver appears in fusion of a darkbrownish colour. After it has been kept melted for acertain time, a part of the sulphur having escaped fromthe top, the surface becomes white, and some bright dropsof silver, about the size of peas, are perceived on it. Whenthis happens, which is commonly in about three hoursafter the last addition of the reserved grains, sooner or lateraccording as the crucible has been less or more closelycovered, and the matter more or less stirred, the fire mustbe immediately discontinued •, for otherwise more and moreof the silver, thus losing its sulphur, would subside, andmingle with the part at the bottom in which the gold iscollected. The whole is poured out into an iron mortargreased and duly heated ; or if the quantity is too large tobe safely lifted at once, a part is first laded out from thetop with a small crucible, and the rest poured into themortar. The gold, diffused at first through the wholemass, is now found collected into a part of it at the bot-tom, amounting only to about as much as was reservedunsulphurated. This part may be separated from the sul-phurated silver above it by a chisel and hammer; or moreperfectly, the surface of the lower mass being generallyrugged and unequal, by placing the whole mass, with itsbottom upwards, in a crucible : the sulphurated part quicklymelts, leaving unmelted that which contains the gold,which may thus be completely separated from the other.The sulphurated silver is assayed, by keeping a portion ofit in fusion in an open crucible, till the sulphur is dissi-pated, and then dissolving it in aqua fortis: if it shouldstill be found to contain any gold, it is melted again, asmuch more unsulphurated silver added, as was employedin each of the former injections, and the fusion continuedabout an hour and a half.

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