IMPROVEMENTS IN THE SEPARATION. OF GOLD FROM CERTAIN AURIFEROUS MIXTURES, COMPOUNDS, AND PRODUCTS
Year: 1857

page_text: LETTERS PATENT to Astley Paston Price, of Margate, in the County of
Kent, Chemist, for the. Invention of "IMPROVEMENTS IN THE SEPARATION.
OF GOLD FROM CERTAIN AURIFEROUS MIXTURES, COMPOUNDS, AND PRODUCTS."
Sealed the 24th March 1857, and dated the 31st January 1857.
PROVISIONAL SPECIFICATION left by the said Astley Paston Price at
the Office of the Commissioners of Patents, with his Petition, on the
31st January 1857.
I, ASTLEY PASTON PRICE, of Margate, in the County of Kent, Chemist, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN THE
SEPARATION OF GOLD FROM CERTAIN AURIFEROUS MIXTURES, COMPOUNDS, AND
PRODUCTS," to be as follows:-
My said Invention consists of a mode or modes of treating certain
auriferous matters, compounds, and products, such as contain gold, alloys of
gold, or other auriferous materials, consisting of gold alloyed or mixed with
iron, copper, nickel, cobalt, silver, zinc, lead, and tin, or any of them, or any
compounds or combinations thereof, for the purpose of separating and
obtaining the gold. separate from the other substances with which it is alloyed
or mixed.
For this purpose, I convert such compound mixtures or products into a
regulus of artificial sulphurets, consisting essentially of sulphuret of iron or
copper, or any combinations thereof, and which regulus will contain- the
whole or practically the whole of the gold contained in the original products,
compounds, or mixtures by fusion in a suitable furnace, with suitable fluxes,
together with suitable sulphur, or sulphuretted metallic or other compounds
or materials. Should the compounds or products to be treated not contain

page_text: sufficient of such sulphuretted compounds as to form the required auriferous
regulus of artificial. sulphurets, but should the compounds,. products, or
mixtures contain or be mixed with a sufficient proportion of sulphuret of
copper or iron, or combinations thereof, so as to form when subjected to
fusion with suitable fluxes such a regulus as before mentioned, then I subject
them to fusion with suitable fluxes without the addition of the before-
mentioned sulphuretted compounds. If the compounds, mixtures, or pro-
ducts to be treated contain earthy, siliceous, or similar matters, I add such
fluxes as will enable ime by fusion to separate them from the regulus of
sulphurets contained in or produced by or from the compounds, products,
or mixtures, treated or operated upon as before described.
.
Now, in order to obtain the gold from such regulus, or from similar
artificial sulphuretted compounds, I subject such regulus, or similar com-
pounds, of artificial sulphurets containing any of the above-mentioned metals,
together with gold, to calcination, either with or without the addition of
common salt, or of other suitable chlorides, so as to convert the sulphurets
with which the gold is mixed into oxides or chlorides, and to render the gold
capable of entering into combination and forming a soluble compound with
chlorine. I then subject the product thus obtained to the action of chlorine
either in a gaseous state or in solution. If gaseous chlorine be used, then I add
water during the operation or afterwards, to dissolve the gold compound. I
also produce the same effect by the employment of certain hypochlorites in
conjunction with an acid or acids, so as to liberate a solvent agent for the
gold.
The gold having been thus obtained in solution, I precipitate it from such.
solution by means of protosulphate of iron, sulphuretted hydrogen, or other
known or suitable precipitants of gold.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Astley Paston Price in the Great Seal Patent Office on the
31st July 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ASTLEY
PASTON PRICE, of Margate, in the County of Kent, Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of January, in the year of our Lord
One thousand eight hundred and fifty-seven,.in the twentieth year of Her

page_text: reign, did, for Herself,. Her heirs and successors, give and grant unto me,.
the said Astley Paston Price, Her special license that I, the said Astley
Paston Price, my exécutors, administrators, and assigns, or such others as I,-
the said Astley Paston Price, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at
all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE SEPARATION OF GOLD FROM CERTAIN AURIFEROUS MIXTURES,
COMPOUNDS, AND PRODUCTS," upon the condition (amongst others) that I, the
said Astley Paston Price, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Astley. Paston Price, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement:—
Before describing my Invention, I will state that I am aware that it has
been proposed to separate gold from certain auriferous ores by the employ-
ment of a process which consists essentially in subjecting certain auriferous
ores to calcination or roasting, so as to obtain oxides of the metals and
metallic gold, which, when in such metallic state, is to be dissolved out and
separated by means of a solution of chlorine, or by means of chlorine gas
and water. Such a process is applicable to certain ores only, and cannot
advantageously be applied to ores which contain calcareous, earthy, or other
ingredients which may be acted on by chlorine, neither can gold be separated
advantageously by the before-mentioned process or other similar process from
alloys or other metallic compounds of gold.
Now, one of the objects of my Invention is to extract and separate the
gold from such auriferous mixtures, compounds, and products as cannot
advantageously be treated directly by the before-mentioned or other similar
process; and in order to effect the same I proceed as follows:-I convert
such auriferous mixtures, compounds, or products into a regulus in the
manner herein-after.described, and I prefer that such auriferous regulus
should consist essentially of sulphuret of iron or sulphuret of copper, or
mixtures or compounds of the same, and I prefer that in the formation or
production of such auriferous regulus the proportion of regulus so formed,

page_text: resulting, or produced, should bear such a proportion to the precious metal
to be extracted as that the slag or scorice shall be as poor in gold as
possible.
Now, what I mean and wish to be understood by the conversion of such
auriferous mixtures, compounds, or products into a regulus is, that I place
them in a suitable furnace, and should they contain earthy, silicious, or other
matters which it may be advisable to get rid of, I place along witli them in
the furnace suitable fluxes, so as to produce by fusion what is termed a slag,
and to slag them off or separate them in such a manner as is well understood
by metallurgists.
Should the auriferous mixtures, compounds, or products not contain
sufficient sulphuret of copper, sulphuret of iron; or mixtures or compounds
of the same, so as to form when subjected to such smelting operation for the
purposes of separating the foreign ingredients and the obtaining of or the
conversion of the same into a regulus, then I add either sulphuret of copper
or sulphuret of iron, or a mixture of them or their compounds, or such other
sulphur materials as will produce in such smelting operations an auriferous
regulus consisting essentially of sulphuret of copper or sulphuret of iron, or
mixtures or compounds of the same.
The operation and the necessary requirements for producing a regulus
from sulphureted materials, or from a combination of non-sulphuretted and
sulphuretted materials, are well understood by metallurgists; and in order to
illustrate the production of such an auriferous regulus, I may instance the
production of an argentiferous iron or copper regulus or. argentiferous iron
and copper regulus obtained or produced in the smelting of silver orës or
other argentiferous materials in conjunction with sulphuret of iron or
sulphuret of copper as explaining what I mean, and wish to be understood
by the conversion of the auriferous compounds, mixtures, and products into a
regulus, which auriferous regulus, as before stated, I prefer should consist
essentially of sulphurets of iron or copper, or mixtures or compounds of the
same. Such auriferous regulus, or any similar artificial sulphuretted com-
pound or regulus, I reduce to a state of division, and I prefer that the same
should be finely ground previously to being subjected to calcination.
in
The operation of calcination may be conducted in the ordinary calciners; ór
any suitable calcining furnace, care being taken that the heat be carefully
regulated until the larger portion of the sulphur has been expelled. The
calcination is then carried on until the whole or practically the whole of the
sulphur shall have been expelled or oxidized, and the residue shall essentially
consist of oxides of the metals, and the gold shall have been converted into a

page_text: condition or state capable of being acted on and dissolved out by means of
chlorine and water, or of an aqueous solution of chlorine, or by means of a
solution of an acidulated: hypochlorite. The calcined or partially calcined
regulus may be submitted to calcination with salt, or to what is termed the
salting process; and I prefer to perform this operation in a manner similar to that
adopted in the treatment of calcined or partially calcined argentiferous regulus;
by what is called the "Augustin process." Should the auriferous regulus
contain silver, then I prefer to proceed either with the calcination, as before
described, or I calcine the auriferous sulphuretted material until the whole or
the larger proportion of the sulphuret of silver shall have been oxidized and con-
verted into sulphate of silver; and in order to effect this, I proceed in a manner
well understood and at present adopted in the extraction of silver from argen-
tiferous copper or iron regulus, or from argentiferous copper and iron regulus.
The sulphate of silver so produced may be extracted or dissolved out by
means of hot water, and the silver be therefrom precipitated by means of
copper or otherwise, as is well understood. The washed residue of the calcined
regulus may then be replaced in the calciner and be recalcined until perfectly
sweet; or it may be subjected to the process of calcination with salt, or to what
is called the salting process, as before mentioned; or it may be subjected if
calcined sufficiently sweet. to the action of chlorine, in manner herein-after
described.
1
The calcined auriferous sulphuretted material resulting from either of the
before-mentioned processes of calcination is, in order that the gold may be
extracted therefrom, to be placed when cold or nearly so in suitable vessels,
and subjected to the action of an aqueous solution of chlorine. The said
solution is made to percolate through the material until the solution escaping
from the bottom of the percolating vessel contains practically no gold.
The solution and washing out of the gold may be effected in vessels made
of earthenware, stoneware, or wood lined with pitch, asphalte, gutta percha, or
any other substance not materially acted upon by the solution of chlorine, nor
capable of causing the precipitation of gold from such solution in chlorine;
the vessels I prefer are those which are in form similar to an open cask, or a
cask-shaped vessel provided with a moveable head or cover, and also with
suitable inlet and outlet pipes, so as to allow the solution of chlorine to enter
and escape. These vessels are provided with a false bottom, on which is or
may be placed a layer either of coarse sand or other suitable material, so as
to support a piece of gutta percha or other suitable substitute, on which is to
be placed the calcined material to be operated on.. The piece of gutta
percha or substitute should be perforated in such a manner as to allow a free

page_text: .
passage to the percolating solution. When gaseous chlorine is employed to
convert the gold contained in the calcined regulus into chloride of gold, the
regulus to be operated on is placed in a vessel or apparatus similar to that
before described, but so constructed that the same may be partially or entirely
closed. The apparatus is provided with suitable inlet and outlet pipes, and the
gaseous chlorine may, by preference, be made to enter at the upper part of the
vessel or apparatus. Previous to and during the admission of the chlorine
water is made to percolate through the calcined regulus, and the solution of
gold resulting from such operation is allowed to escape' by a suitable exit pipe
placed at the bottom of the vessel.
I have stated that the gold may be dissolved and separated from the before-
mentioned calcined regulus by means of an acidified solution of an hypochlorite:
That which I prefer, on account of its cheapness, is the hypochlorite of lime;
such a solution is acidulated with a suitable acid, such as sulphuric or. hydro-
chloric, the latter acid being preferred: The dilute acidified solution of an
hypochlorite when employed to dissolve and separate the gold is made to
percolate through the calcined regulus, contained in an apparatus similar to
that before described, until the solution escaping at the bottom of the vessel
contains practically no gold.
The solution of gold obtained by either of the above methods is allowed to
collect in tanks or cisterns of suitable size, lined with asphalte, pitch, gutta
percha, or other suitable material; and the gold may be therefrom precipitated
by means of protosulphate of iron, or any other known reducing or pre-
cipitating agent.
The calcined regulus, after having been subjected to either of the processes
before mentioned for the separation of the gold, 'is to be washed with water in
order that the last traces of the solution of gold may be washed out and
obtained. The dilute solutions may be collected in suitable tanks, and the
gold be therefrom precipitated by means of protosulphate of iron, or any other
known precipitating agent.
The precipitate of gold after having been collected should, if it be con-
taminated with impurities, be purified from the same by cupellation with lead,
in a manner well understood by metallurgists; or if it contain silver and it is
desired to separate the same therefrom, the gold is to be dissolved by means of
a mixture of nitric and hydrochloric acids, and may be precipitated there-
from by means of protosulphate of iron, or other precipitating agent; or the
silver may be separated by any known method. Should the calcined auriferous
regulus, after having been subjected to the action of chlorine still contain gold,
the same may again be subjected to fusion with suitable fluxes and sulphuretted

page_text: materials, so as to separate and obtain the gold therefrom in the state of an
auriferous regulus, in a manner similar to that well understood and practised
in the formation and concentration of argentiferous, regulus from residual,
calcined, and washed argentiferous copper and iron regulus.
Should, as may sometimes occur, the slags resulting from the formation of
the auriferous regulus contain gold, they are again to be submitted to another
smelting operation in a suitable furnace, with suitable fluxes, together with
the addition of copper or iron pyrites, or other sulphur materials capable of
producing the desired auriferous iron and copper regulus.
The silver and copper contained in the residue after the extraction of the
gold may be extracted and separated therefrom by any of the processes
generally adopted for the extraction of silver and copper.
Now, what I claim as the Invention secured to me by the herein-before in
part recited Letters Patent is,―
First, the before-described treatment of certain auriferous compounds,
mixtures, and products in order to obtain gold therefrom, by converting the
same into an auriferous regulus, or into an artificially prepared sulphuretted
auriferous compound or regulus, consisting, essentially, by preference, of either
sulphuret of iron or sulphuret of copper, or mixtures or compounds thereof,
and the subjecting the same to calcination either with or without the addition
of salt, and the extraction and separation of the gold therefrom by the employ-
ment of an aqueous solution of chlorine, or of chlorine and water, or of a
solution of an acidified hypochlorite, from which solutions the gold is or may
be precipitated by protosulphate of iron or other precipitating agent.
Second, the extraction of gold from any artificially prepared sulphuretted
auriferous compound or regulus, consisting essentially of sulphuret of iron or
sulphuret of copper, or mixtures or compounds thereof, as is herein-before
referred to, the same being calcined as aforesaid by means of chlorine and
water; or of an aqueous solution of chlorine, or of a solution of an hypochlorite
in conjunction with an acid, so as to liberate a solvent for the gold, the gold
being afterwards precipitated therefrom by means of protosulphate of iron or
other precipitating agent.
In witness whereof, I have hereunto set my hand and seal, this Thirty-
On the eight hundred
ASTLEY PASTON PRICE (L.S.)