Year: 1888

page_text: Date of Application, 22nd Mar., 1888
Complete Left, 5th June, 1888
Complete Accepted, 6th July, 1888
[Communicated from abroad by MARC MAURICE ROTTEN, of Shiffbauerdamm,
29, Berlin, in the Empire of Germany, Engineer.]
I, CHARLES DENTON ABEL, of No. 28 Southampton Buildings, Chancery Lane, in
the County of Middlesex, Consulting Engineer and Patent Agent, do hereby declare
he nature of this invention to be as follows:-
When gold is contained in gold bearing minerals in such a finely divided state that
It cannot be extracted by the washing and amalgamating process, the chlorine process
has hitherto been employed, in which the chlorine is produced either by chemical or
electrolytic methods. This process however is subject to serious disadvantages. In
the first place the chlorine only acts as a solvent on the gold after all the more easily
soluble metals or metallic compounds have been previously dissolved, involving a large
expenditure of chlorine or complicated preparatory processes which can often not be
carried on at the same works.
Furthermore, the chloride of gold is a compound that is easily decomposed, involving
considerable loss of gold in its separation.
These disadvantages are, according to the present invention, in a great measure
obviated by employing, in place of chlorine a dilute alkaline or neutral solution of
potassium cyanide, which dissolves the gold out of the finely divided minerals or ores
carrying the same, and which can be separated from the residue without loss
of gold.
The separation of the gold from the solution obtained can be effected by chemical
methods, but it is preferable to effect the precipitation thereof by electrolysis, in which
case carbon, iron, or other metals may be used as anodes.
In order to enrich the solution as much as possible for this galvanic separation
process, it can be employed repeatedly in the known manner to act upon fresh quantities
of ores.

page_text: After separating the gold, the solution, after making good the cyanogen expended,
can be used again for fresh extractions until it has become unserviceable by reason of
iis having taken up too large a quantity of metals that cannot be separated by
electrolysis.
'
The cyanogen contained in such spent solutions may then be regained by chemical
means. If the ores contain metallic compounds that are soluble in potassium
cyanide, it is of advantage to separate these by suitable solvents before extracting
the gold.
The above described method is also applicable for the extraction of other precious
metals that form soluble double salts with cyanogen, such as platinum, silver,
mercury, &c.

page_text: from Minerals and Ores Containing them.
I, CHARLES DENTON ABEL of No. 28 Southampton Buildings, Chancery Lane in
the County of Middlesex, Consulting Engineer and Patent Agent do hereby declare
the nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
When gold is contained in gold-bearing minerals in such a finely divided state that
it cannot be extracted by the washing and amalgamating process, the chlorine process
has hitherto been employed, in which the chlorine is produced either by chemical or
electrolytic methods. This process however is subject to serious disadvantages. In
the first place the chlorine only acts as a solvent on the gold after all the more easily
soluble metals or metallic compounds have been previously dissolved, involving a large
expenditure of chlorine or complicated preparatory processes, which can often not be
carried on at the same works. Furthermore, the chloride of gold is a compound that
is easily decomposed, involving considerable loss of gold in its separation.
These disadvantages are, according to the present invention, in a great measure
obviated by employing, in place of chlorine, a dilute alkaline or neutral solution of
potassium cyanide, which dissolves the gold out of the finely divided minerals or ores
carrying the same, and which can be separated from the residue without loss
of gold.
The separation of the gold from the solution obtained can be effected by chemical
methods, but it is preferable to effect the precipitation thereof by electrolysis, in which
case carbon, iron or other metals may be used as anodes. In order to enrich the
solution as much as possible for this galvanic separation process, it can be employed
repeatedly in the known manner to act upon fresh quantities of ores.
After separating the gold, the solution, after making good the cyanogen expended,
can be used again for fresh extractions until it has become unserviceable by reason of
its having taken taken up too large a quantity of metals that cannot be separated by
electrolysis. The cyanogen contained in such spent solutions may then be regained
by chemical means.
If the ores contain metallic compounds that are soluble in potassium cyanide, it is
of advantage to separate these by suitable solvents, before extracting the gold.
The above described method is also applicable for the extraction of other precious
metals that form soluble double salts with cyanogen, such as platinum, silver,
mercury &c.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. The method of extracting gold and other precious metals from minerals or ores
containing them by dissolving the same from the pulverised minerals or ores by means
of an alkaline or a neutral solution of potassium cyanide, or other cyanogen salts,
substantially as herein described.
2. The use of lyes containing precious metals, produced as referred to in the previous
claim, for the separation of precious metals by electrolysis.
ABEL & IMRAY,
Agents for the Applicant.