US392929A - Alexandeb paekes - Google Patents

Description

llnrran STATES ATENT Orrrca,

ALEXANDER PARKES, OF DULWICH, COUNTY OF SURREY, ENGLAND.

PROCESS OF EXTRACTING GOLD AND OTHER METALS FROM SULPHIDE ORES 0R COMPOUNDS CONTAINING THE SAME.

SPECIFICATION forming part of Letters Patent No. 392,929, dated November 13, 1888.

Application filed April 12, 1887. Serial No. 234,546. (No specimens) Patented in England October 13, 1886, No. 13,073 in Queensland May 4, 1887, No. 349; in Italy September 9, 1887, XLIV, 56; in France September 10,1887, No. 185,753; in Belgium September 13, 1887, No. 78,869; in Germany September 15, 1887, No. 3,449 in Spain September 16, 1887,-in India October 8, 1887, No. 308; in Canada October 13, 1887, No. 45,418; in New Zealand October 17,1887, No. 2,584; in Victoria October 28, 1887, No. 5,405; in New South Wales October 31, 1887, No. 305; in South Australia November 3, 1887; in Cape Colony November 8, 1887, 414; in Natal November 16,1887; in Portugal November 18, 1887, No. 1,322; in Tasmania November 21, 1887, No. 509,

and in Brazil November 30, 1887, No. 537.

To aZZ whom it may concern.-

Be it known that I, ALEXANDER PARKES, a subject of the Queen of Great Britain and Ireland, residing at 8 Chancellor Road, Dulwich, in the county of Surrey, England, have invented certain new and useful Improvements in Extracting Gold and other Metals from Sulphide Ores or Compounds Containing the Same, (for which I have obtained Letters Patent in Great Britain, No. 13,073, dated October 13, 1886; Italy, September 9, 1887 N o. 56, Vol. XLIV; France, September 10,1887, No. 185,753; Belgium, September 13, 1887, No. 78,869; Germany, September 15, 1887, No. 3,449--Letters Patent allowed but not yet issued; British India, October 8, 1887, No. 308; New Zealand, October 17, 1887, No. 2,584; Victoria, October 28, 1887, No. 5,405; New South Wales, October 31, 1887 No. 305; Cape Colony, November 8, 1887, folio 414; Natal, November 16, 1887 Tasmania, November 21, 1887, No. 509; Brazil, November 30, 1887, No. 537; Queensland, May 4, 1877, No. 349-Letters Patent not yet granted; Spain, September 16, 1887; Canada,0ctober 13, 1887, No. 4.5,418Letters Patent not yet granted; South Australia, November 3, 1887, and Portugal, November 18, 1887, No.1,322-Letters Patent not yet granted;) and I do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to the treatment of auriferous ores of the sulphide class for the extraction of the gold, silver, and other metals contained therein by means of an economical and expeditious process which enables, practically, the whole of the precious metals to be separated, and whereby the usual preliminary operation of calcining the ore is dispensed with.

In treating refractory ores of the class above referred to, and which frequently contain gold, silver, copper, and other metals, I crush or granulate the ore and melt it in a reverbera tory or other suitable furnace with fluxes composed, by preference, of alkaline or earthy sulphates or chlorides, and containing carbon or to which carbon is added. To the mixture of ore and flux is added lead or oxidized or sulphur compounds of lead,with the object of collecting all the precious and other metals sought to be recovered. These completely separate from the slag, and, the latter having been removed,a metallic compound is obtained in a condition suitable for treatment by what is known as Parkes desilverizing process, or by other known methods for separating the gold and other metals contained in such compound. In some instances the ore in its natural stat contains sufficient lead to render the addition,

as above mentioned, of lead or oxidized or sulphur compounds of lead unnecessary, in which case a sufficient quantity of the lead naturally contained in the ore is reduced and combines with and serves to collect the gold (and silver, if any) contained in the ore.

Instead of adding lead in the furnace, as above described, a regulus may be obtained as the result of the process of smelting the mixture of ore and flux, and this regulus may be treated with lead or the compounds of lead before mentioned.

The regulus obtained as the result of smelting sulphide ores with the compound flux of the kind hereinbefore specified possesses the peculiar property or tendency to disintegrate and resolve itself into a fine powder by more exposure for a few hours to the atmosphere. This effect, which resembles that to which quicklime is subject, may be expedited by sprinkling the regulus, while hot, with water. In such finelydivided state the regulus is specially adapted for treatment with lead or by other known methods for separating the gold and other metals containedtherein. Furthermore, the metallic sulphides being collected in a concentrated mass, the quantity of material or regulus requiring further treatment is of comparatively small bulk.

The particular fluxing substances most appropriate for different kinds of ore will vary to some extent according to whether the ores are combined with silicious or other earthy matters. The proportions in which the fluxing substances are used will also be subject to variation.

In applying my improved process, by way of example, to ores such as are obtained from the Ravenswood mines of Queensland, I employ, for each ton of such ore, three to four hundred-weight of caustic lime, (by preference,) in combination with either one hundred-Wei ght of caustic soda or the same quantity of sulphate or bisulphate of soda,or half that quantity of silicate of soda, from one-half to one hundred weight of carbon being added.

Instead of a reverberatory furnace, a cupola or blast furnace may be employed for melting the ore; but in any case I regard it not merely as unnecessary, but as undesirable, that the ore should be subjected in the first instance to calcination for the purpose of driving off the sulphur contained therein. I have found that Without calcining the ore the metals reduced separate very perfectly from the slag, and that the latter is left remarkably free of the precious metals. Furthermore, by my improved process, the use both of amalgamation and of chlorination may be dispensed with, an improved result being at the same time attained.

The ore may with advantage be crushed to a moderate size before being placed in the furnace; but the usual. process of grinding it to a fine powder is rendered unnecessary.

I also regard as an important feature of my invention the use, in combination with caustic lime or limestone, of caustic soda, or nitrate, silicate, or carbonate of soda,or sulphur compounds of soda, the same being employed in conjunction with carbon, loss of gold and silver being prevented by the use of such fluXing substances in combination. They also react upon one another in such a manner as to produce great fluidity and to permit of a given quantity of refractory ore being treated with a far smaller quantity of fiux than by any laboratory or other process with which I am acquainted, my improved process being thereby rendered commercially practicable.

Having now fully described my invention, what I desire to claim and secure by Letters In testimonywhereofl have signed my name to this specification in the presence of two subscribing witnesses.

ALEXANDER PARKES.

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JAMES W. SDLYL'LHAN, O. XV. Lnns.