IMPROVEMENTS IN TREATING METALLIC ORES OR OTHER MATTERS CONTAINING METALS FOR THE SEPARATION OF THE METALS THEREFROM
Year: 1883

page_text: LETTERS PATENT to John Henry Johnson, of 47 Lincolns Inn Fields, in the
County of Middlesex, Gentleman, for an Invention of "IMPROVEMENTS IN
TREATING METALLIC ORES OR OTHER MATTERS CONTAINING METALS FOR THE
SEPARATION OF THE METALS THEREFROM communicated to him from Albert
Daniel Ancel and Jean-Marie Antonin Thiollier persons resident at Paris in
the Republic of France
"
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 20th February 1883.
"
JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman "IMPROVEMENTS IN TREATING METALLIC ORES OR OTHER MATTERS
CONTAINING METALS FOR THE SEPARATION OF THE METALS THEREFROM "a com-
munication to me from Albert Daniel Ancel and Jean-Marie Antonin Thiollier
persons resident at Paris in the Republic of France
This invention relates to the extraction of metals from metalliferous substances
by the employment of electricity and it consists in causing the ore itself to act
as a soluble electrode immersed in a liquid capable of acting upon the metal as
hereinafter described. This liquid is so constituted that under the influence of an
electric current the bodies transferred to the pole formed by the ore dissolve the
metallic matter contained in the latter.
When the ore is employed as a positive electrode the metals or metallio
compounds therein contained are dissolved and under the decomposing influence of
electricity the metals are transferred to the negative pole where they are deposited
in a pure metallic state as hereinafter explained.
When the ore is employed as a negative electrode the metals or metallic
compounds are dissolved and the metals are transferred to the positive pole in the
condition of oxide or acid.
The electricity necessary for the application of the improved process may be
obtained from any convenient source-such as a galvanic or other battery or from a
magneto or dynamo electric machine

page_text: The intensity of the current is regulated according to the nature of the ores and
the resistance opposed by the bath to the decomposition resulting from the
elements of which it is composed
The liquid in which the ore is immersed consists of a solution of an acid a base
or a salt and the nature of the materials of which it is composed varies according
to the composition of the ores or materials to be treated.
The apparatus hereinafter described is equally well adapted for treating metallic
substances, ores, matts, complex metals and the like from which it is necessary to
extract the valuable metallic portions or elements by means of electricity
This apparatus consists of a. trough or tank for the reception of the chemical
bath or liquid herein before referred to and in which are immersed suitable
receptacles containing the ore-These receptacles may be made of wood wicker
work, porous earthenware or other suitable materials and are preferably in the form
of an elongated rectangle in cross section.
When the receptacles are constructed of non-porous materials the two large sides
are perforated and the perforations are made as small and as near together as
possible so as to allow of an unimpeded circulation of the liquid and at the same
time support or retain the ore
In some cases when the ore requires to be very finely ground the two perforated
sides of the receptacles may be lined with a woven fabric
For this purpose a sufficient space must be left between the bottoms of the
receptacles containing the ore and the bottom of the vessel containing the bath
The receptacles may be open at the top and one side is capable of being removed
to facilitate the removal of the ore which during the treatment will have become
somewhat agglomerated
In order to connect the ore with the positive or negative pole of the battery or
other source of electricity conducting electrodes proof against the action of the
liquid such as retort carbon, coke or plumbago for example are introduced into the
body of the ore The proper material to employ for this purpose varies according
to the nature of the bath as is well understood by electro chemists but metal is
seldom employed except as a negative electrode
Pulverised plumbago agglomerated with about ten per cent of clay and made
into blocks or slabs of suitable dimeusions which are afterwards baked in the
same manner as ordinary bricks forms an anode sufficiently proof against the
chemical action and possessing sufficient conductivity-When the ore is a bad
conductor it should be mixed with fragments of coke retort carbon or plumbago
in addition to the slabs which are introduced into the mass of ore-By these
means the current is distributed throughout the ore and the separation of the
metallic matter is facilitated-The fragments referred to being larger than the
particles of pulverised. ore may be subsequently separated by sifting with water
and used again
Under these conditions the plumbago electrodes and the ore form practically a
solid mass in which under the influence of a current of sufficient intensity all the
parts (such as the metals and the combinations of metals with metalloids) that are
not proof against the action of the chemical agents are dissolved and eliminated-
The electrodes thus connected with the ore communicate with a metal frame
preferably of copper which is joined to one of the poles of the battery or machine
The metals or metallic substances extracted from the ores are deposited on plates
suspended in close proximity to the poroas or perforated sides of the receptacles
containing the ore When the ore acts as a positive electrode the plates are of metal,
preferably copper-The metals extracted from the ore are deposited on these
plates in a pure metallic state sometimes solid sometimes pulverulent an all
these plates communicate with a copper frame which in turn communicates with
the negative pole
When the ore acts as a negative electrode the plates which receive the deposit of
metallic matter are preferably composed of plumbago and are connected by a
copper frame with the positive pole of the battery or other source of electricity

page_text: Small receptacles composed of lead or wood should be arranged underneath the
receiving electrodes for the reception of the metallic particles that become detached
from the latter-In some cases it will be advantageous to raise the temperature of
the bath to a point approaching ebullition in order to facilitate and accelerate the
decomposition of the ore by the chemical agents and the deposit of the metallio
matter For this purpose steam is caused to circulate in a lend or copper worm
arranged at the bottom of the vessel; the temperature must not however be raised
quite to boiling point as this would set up an agitation of the liquid that would
prejudice the success of the operation
After the action of the current has proceeded for a certain time and it has been
ascertained by testing a sample or otherwise that the ore no longer contains any of
the metal or metals which are to be extracted by means of the operation the
receptacles which now contain only the gangues are removed and emptied-When
it is desirable to preserve the liquid or when the ore still contains valuable matter
which is capable of being subsequently extracted by putting it into a chemical bath
of a different composition to the first, this matter is submitted to lixivation in the
ordinary manner
The electrodes upon which the metals or metallic matter has been deposited are
removed from the bath from time to time and separated from the matter adhering
to their surfaces
The liquid composing the bath is drawn off occasionally and allowed to settle in
a tank and after removing the accumulation of ore dust from the bottom of the
vessel the latter is refilled with clear liquid by means of pumps
The time occupied by the operation varies according to the nature of the ore
from a few hours to several days-Ores containing metals combined with metalloids
such as sulphur, arsenic, tellurium and the like requires more time than other ores
as a part of the electric force is expended in producing the oxygen necessary for the
conversion of these materials into soluble salts-An excess of hydrogen is also
evolved at the negative pole which impedes the regular deposit of metal-It is
consequently advisable to roast the ore when possible with great care in order to
drive off the greater part of the metalloids
°
The acids pass to the positive pole and in presence of the nascent oxygen which
is formed at this pole act with great rapidity on the metallic portion of the ore
when the latter is arranged as a soluble positive electrode
The metallic oxides are subsequently attracted by the negative electrodes and
are reduced by the nascent hydrogen formed thereon and are deposited upon these
electrodes in a pure metallic state
When the ore constitutes the negative electrode the metallic matter is quickly
acted on by the bases which pass to this pole when the salt employed in the bath
is a salt of potassa, soda or ammonia-When the ore contains substances such as
sulphides tellurides arsenides and the like that are not readily acted upon by acids
oven when employed under the influence of electricity it is necessary that the
metal to be dissolved should be capable of readily forming a soluble combination
with the base employed
In certain cases it is advantageous to employ ammonia but it is generally
preferable to employ carbonate of ammonia-It is often advantageous to employ
bases in preference to salts and acids because bases form with the metals somewhat
unstable salts that are very readily decomposed by electricity
In applying this Invention to the treatment of ore containing silver alone in the
native state it is preferable to employ a bath composed of ammonia or carbonate of
aminonia or a sulphate or nitrate of soda or soluble cyanide-Sea salt may also be
employed but in this case it is advisable to heat the solution
When the ore contains gold or platinum alone the bath may be composed of
sulphates nitrates soluble cyanides and the like-Chloride of Sodium is to be
preferred in practice as n salt but the best results are obtained by a bath formed of
solution of soda or potash-When the ore contains two or three of these metals
(gold, silver or platinum) it is preferably treated in a solution of sea salt

page_text: Ammonia and next to Ammonia carbonate of Ammonia forms the best bath for
ore containing chloride and sulphide of silver-Good results may also be obtained
by employing a concentrated solution of Chloride of Sodium at an elevated
temperature
In the case of ore containing telluride of Gold sea salt or cyanide of potassium
may be employed the telluride being placed at the positive pole-The ore may
constitute the negative pole in which case the soda which passes to the negative pole
acts speedily on the telluride and the Gold is carried to the positive pole in the
condition of auric acid from which pure Gold may be obtained by melting with
carbon and borax
When Gold and Silver exist in the ore simultaneously with lead, copper or iron
and these metals are combined with metalloids such as sulphur, chloride, arsenic
tellurium and the like a heated solution of Chloride of Sodium is employed-With
a moderate current the gold, silver, copper and lead are collected at the negative
pole and the iron falls to the bottom of the vessel in the condition of oxide
The materials may be first treated in a bath of potash for the extraction of the
gold and lead which are then separated by cupellation, subsequently treating the
said materials in an ammoniacal bath to extract the silver and copper
To extract zinc from calamine or carbonates the carbonate must be previously
reduced by calcination to the condition of oxide-Blende is a sulphide of zinc
usually mixed with sulphides of iron and lead and should be roasted carefully to
bring it to the same condition as the calamine
The ore is employed as a soluble positive pole in a bath composed of alkaline,
saline or preferably of basic materials such as ammonia or carbonate of ammonia
The zinc obtained by this process is extremely flexible and ductile-This process
also enables iron to be galvanised with zinc direct from the ore.
To extract aluminium from clay bauxite and other aluminiferous substances the
bath is preferably composed of a concentrated solution of chloride of aluminium
double chloride of sodium and aluminium or double chloride of aluminium and
.ammonium with a powerful current of electricity-The bath may also consist of a
concentrated solution of soda or potash or a saturated bath of aluminate of soda
In applying this invention to the manufacture of magnesium, artificial carbonate
of magnesia is preferably employed as the raw material, being obtained by
precipitating natural salts of magnesia by means of carbonate of soda-When this
inaterial is employed it is placed in porous receptacles in the bath and being
dissolved without leaving any residue the operation of removing the receptacles for
the purpose of emptying the same may be dispensed with A concentrated solution
of chloride of magnesium or of magnesium and sodium or ammoniumn is preferably
employed as a bath
To extract lead from its ore a heated bath of marine salt or preferably a solution
of chloride of lead raised to nearly boiling point is employed
This process may be very advantageously applied to the separation of silver from
lead The argentiferous lead is melted with a small quantity of zinc and the alloy
of lead silver and zinc which is formed at the surface during the cooling is placed
in the receptacles of the electrical apparatus herein before described-A bath of
sulphate of zinc or preferably carbonate of ammonia is employed The zinc alone is
dissolved and is deposited in a pure condition on the negative electrode. The lead
and silver are separated by cupellation. The cost of distillation and the waste of
zinc and silver which it involves are thus avoided
Ores c
s containing antimony are treated in a heated solution of potash or a saline
bath containing acids capable of forming soluble salts with antimony
Mercury is obtained by treating the cinnabar in an alkaline bath or preferably
in a bath of sulphate, nitrate or bichloride of mercury
Cupreous ores such as oxides and carbonates are preferably treated in an
ammoniacal or saline bath-Grey copper ores containing arsenic or antimonium are
roasted at a low temperature without driving off the antimony and treated in a
bath of potash as hereinbefore described with reference to antimony-The residue

page_text: from the operation is treated in a bath of ammonia or carbonate of ammonia which
extracts the copper and silver
Nickel is extracted from double hydrated silicates of nickel and manganese hy
first calcining the ore so as to reduce the nickel to the metallic state and then
treating it in a saline or preferably an ammoniacal bath. Ores containing . nickel
alloyed with cobalt and sometimes with copper are roasted to drive off the greater
part of the sulphur and arsenic and treated in a bath of potash or preferably soda.
The cobalt alone is dep sited on the negative electrodes in the condition of soluble
cobaltate; the residue is treated in an ainmoniacal bath to extract the nickel and
copper which may be subsequently separated by means of a bath of sulphate of
copper and a weak current which will extract the copper leaving the nickel which
may be fused or be purified by means of electricity in another ammoniacal bath-
Ores such as are found in New Caledonia and in certain parts of the Pyrenees are
mixed with carbon and melted in a furnace to remove the greater part of the
manganese which these ores contain-The alloy of cobalt nickel and manganese
thus obtained is firstly treated by an electric current in a sodic bath to extract the
cobalt and subsequently in an ammoniacal bath to obtain the nickel
In certain localities where the extensive deposits of carbonate of lime and iron
are found in proximity to large falls of water available as motive power iron may
be obtained in a state of chemical purity by the employment of electrical action in
combination with a chemical solution as herein before described such as a bath of
chloride of sodium or of iron for example

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Henry Johnson in the Great Seal Patent Office on the
20th August 1883.
"
a com-
JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman "IMPROVEMENTS IN TREATING METALLIC ORES OR OTHER MATTERS
CONTAINING METALS FOR THE SEPARATION OF THE METALS THEREFROM
munication to me from Albert Daniel Ancel and Jean Marie Antonin Thiollier
persons resident at Paris in the Republic of France
This Invention relates to the extraction of metals from ores by the employment
of electricity and it consists essentially in causing the ore or inetalliferous substance
itself to act as a soluble electrode immersed in a liquid capable of acting upon the
imetal as hereinafter described. This liquid is so constituted that under the
influence of an electric current the bodies transferred to the pole formed by the ore
dissolve the metallic matter contained in the latter.
When the ore is employed as a positive electrode the metals or metallic com-
pounds therein contained are dissolved and under the decomposing influence of
electricity the metals are transferred to the negative pole where they are deposited
in a pure metallic state as hereinafter explained.
When the ore is employed as a negative electrode the metals or metallic com-
pounds are dissolved and the metals are transferred to the positive pole in the
condition of oxide or acid and are subsequently reduced to the metallic state as
hereinafter explained.
The electricity necessary for the application of the improved process may be
obtained from any convenient source such as a galvanic or other battery or from a
magneto or dynamo electric macbine
The intensity of the current is regulated according to the nature of the ores and
the resistance opposed by the bath to the decomposition resulting from the elements
of which it is composed.
The liquid in which the ore is immersed consists of a solution of an acid a base
or a salt and the nature of the materials of which it is composed varies according
to the composition of the ores to be treated as hereinafter explained The baths
best adapted for several ores capable of being treated with great advantage according
to this process are hereinafter described in order to illustrate the application of the
Invention.
The improved apparatus is equally well adapted for treating metallic substances
generally as well as ores matts complex metals and the like from which it is
necessary to extract the valuable metallic portions or elements by means of
electricity.
And in Order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying Drawing is a longitudinal section figure 2 is a
plan and figure 3 is a transverse section of an apparatus constructed according to
this Invention.
The chemical bath or solution is contained in a tank or vessel b of wood but
which may be made of metal if preferred provided that it is properly insulated
from the ground and is not liable to be attacked by the liquid or is suitably
protected from the decomposing action of the latter by varnishing coating or lining.
Wood is to be preferred to metal which is more expensive and always involves
waste of electricity.

page_text: When wooden tanks are employed they are lined internally with lead or as is
preferable for the above reasons with india rubber or caoutchouc to prevent leakage
but when the liquid is an inexpensive one such as some of the liquids hereinafter
described the tanks may be placed on a waterproof floor covered with pitch or sheet
lead and any leakage may thus be collected in a suitable receptacle.
The ore is contained in boxes a constructed of perforated wood wickerwork
porous earthenware or other pervious material and preferably rectangular narrow,
and of small dimensions relatively to the tank. Wood is the best material to
employ in their construction but good results may be obtained in some cases by the
use of receptacls made of wickerwork or porous earthenware or caoutchouc gutta
percha or ebonite may sometimes be employed The receptacles may also be
constructed of metal such as sheet iron enamelled or coated with resin pitch.
caoutchouc or other coating proof against the action of the liquids. These,
receptacles are preferably in the form of a rectangle in cross section as shewn
in the drawing..
i
When the receptacles are constructed of nonporous materials the two sides are
perforated and the perforations are inade as small and as near together as possible
so as to allow of an unimpeded circulation of the liquid and at the same time.
support or retain the ore.
In some cases when the ore requires to be very firmly ground the two perforated
sides of the receptacles may be lined with a woven fabric but as this involves a
qertain waste of electric force it is generally preferable to let some of the ore fall
out on to the bottom of the tank where it may be collected when required. For
this purpose a sufficient space must be left between the bottoms of the receptacles
containing the ore and the bottom of the tank containing the bath. One of the
sides of each box or receptacle a is capable of opening to facilitate the removal of,
the ore which during the treatment will have become somewhat agglomerated
The end of the boxes are provided with handles to facilitate their manipulation
The ore ground or otherwise is introduced into the boxes. Porous receptacles may.
be employed with advantage in the case of ground or pulverised ore.
In order to effectually connect the ore with the positive or negative pole of the
battery or other source of electricity conducting electrodes d proof against the
action of the liquid such as retort carbon coke or plumbago or metal for example
are introduced into the body of the ore.
The proper material to employ for this purpose varies according to the nature of
the bath as is well understood by electro chemists but metal is seldom employed'
except as a negative electrode.
Substances capable of conducting electricity and resisting the action of the
chemical agents are not numerous and are almost exclusively confined to retort
carbon coke, and plombagine or plumbago.
Pulverised plumbago agglomerated with about ten per cent of greasy clay and
made into blocks slabs rods or plates of suitable dimensions which are afterwards
baked in the same manner as ordinary bricks forms an anode sufficiently proof
against the chemical action and possessing sufficient conductivity. When the ore
is a bad conductor it should be mixed with fragments of coke retort carbon or
plumbago in addition to using the rods or plates d which are introduced into the
mass of ore. By these means the current is distributed throughout the ore and
the separation of the metallic matter is facilitated. The fragments referred to
being larger than the particles of pulverised ore may be subsequently separated by
sifting with water and used again.
Under these conditions the plumbago electrodes and the ore form practically a
solid mass in which under the influence of a current of sufficient intensity all the
parts (such as the metals and the combinations of metals with metalloids) that are
not proof against the action of the chemical agents are dissolved and eliminated.
The electrodes d thus introduced-into the ore communicate with a metal frame:
(composed of bars e preferably of copper) which is joined to one of the poles of the
machine or other electrical generator.

page_text: The metals or metallic substances extracted from the ores are deposited on
plates suspended in close proximity to the porous or perforated sides of the
receptacles a containing the ore. When the ore acts as a positive electrode the
plates are of metal preferably copper. The metals extracted from the ore are
deposited on these plates in a pure metallic state sometimes solid sometimes
pulverulent and these plates f are suspended from a copper frame g which in turn
communicates with the negative pole of the generator.
When the ore acts as a negative electrode the plates fare preferably composed of
plumbago and are connected by a copper frame with the positive pole of the
generator.
The boxes or receptacles a filled with ore are placed in the tank b containing the
solution forming the electric bath and arranged as illustrated in figures 1. 2 and 3
of the drawing.
These receptacles are supported at a certain distance, from the bottom upon
wooden chocks or ledges c and the bars e connected to the electrodes d are supported-
by the sides of the tank b
These connections are established by means of clamps binding screws or simple
contact but it is important that the contact should be as perfect as possible and
with this object all the metallic parts of the frames and electrodes that are in
contact are carefully scoured. Under these conditions the vessel b is filled with a
suitable chemical liquid as hereinafter explained and the electric current is caused
to pass The Agents which pass-to the pole formed by the ore dissolve some or all
of metallic parts. When the ore constitutes the positive pole the substances are
deposited on the plates of the negative pole in the condition of pure metal.
When the ore acts as the negative pole the substances are deposited on the plates
of the positive pole in the condition of metallic peroxide but this occurs with but
few ores.
Small receptacles or gutters composed of lead or wood should be arranged under-
neath the receiving electrodes f for the reception of the metallic particles that
become detached from the latter.
The substances which fall off the electrodes f drop into these receptacles and are
thus preserved from mixing with the particles of ore or other matter. at the bottom
of the tank. In some cases it will be advantageous to raise the temperature of the
bath to a point approaching ebullition in order to facilitate and accelerate the
decomposition of the ore by the chemical agents and the deposit of the metallic
matter. For this purpose steam is caused to circulate in a lead or copper worm h
arranged at the bottom of the tank the temperature must not however be raised
quite to boiling point as this would set up an agitation of the liquid that would
prejudice the success of the operation.
After the action of the current has proceeded for a certain time and it has been
ascertained by testing a sample or otherwise that the ore no longer contains any of
the metal or inetals which are to be extracted by means of the operation, the boxes
or receptacles a which now contain only the gangues or matrix are removed and
emptied. This may be accomplished by passing bars of wood or iron through
handles i provided on the ends of the said receptacles and then placing two other
bars at right angles to and underneath the former, thus enabling the whole of the
receptacles to be hoisted out of the vessel by means of pulleys. If the liquid of
the bath is of small value. the receptacles may be opened and the worthless gangues
thrown away but when it is desired to preserve the liquid or when the ore still
contains valuable matter which is capable of being subsequently extracted by
putting it into a chemical bath of a different composition to the first, this matter is
submitted to lixiviation in the ordinary manner.
The Electrodes f upon which the metals or metallic matter has been deposited
are removed from the bath from time to time and separated from the matter
adhering to their surfaces,
The liquid composing the bath is drawn off occasionally and allowed to settle in

page_text: a separate tank and after removing the accumulation of ore dust from the bottom
of the vessel b, the latter is refilled with clear liquid by means of pumps.
The following proportions and dimensions are found to give good results in
practice. The internal dimensions of the tank b are about three yards in length
by about two feet six inches wide and three feet deep. The dimensions of the
boxes a are one foot two inches long by four inches wide and two feet deep
internally. Forty such boxes, each containing about a hundredweight of ore may
be treated in one bath being at the rate of about two tons per bath. A dynamo
machine requiring about fifteen horse power will supply Electricity enough for
about fifty baths thus enabling one hundred tons of ore to be operated upon
simultaneously: The dimensions of the apparatus and strength of current inay
evidently vary however between wide limits according to circumstances, and the
time occupied by the operation also varies (according to the nature of the ore) from
a few hours to several days.
Ores containing metals combined with metalloids, such as sulphur, arsenic,
tellurium and the like, require more time than other ores as a part of the electric
force is expended in producing the oxygen necessary for the conversion of these
materials into soluble salts. An excess of hydrogen is also evolved at the negative
pole which impedes the regular deposit of metal. It is consequently advisable to
roast the ore when possible with great care in order to drive off the greater part of
the metalloids.
The acids pass to the positive pole, and in presence of the nascent oxygen
which
is formed at this pole, act with great rapidity on the metallic portion of the Ore
when the latter is arranged as a soluble positive electrode. The metallic oxides are
subsequently attracted by the negative electrodes and are reduced by the nascent
hydrogen formed thereon and are deposited upon these electrodes in a pure metallic
state. This mode of operating constitutes one of the features of our Invention.
When the Ore constitutes the negative Electrode, the metallic matter is quickly
acted on by the bases which pass to this pole when the Salt employed in the bath
is a Sult of Potassa, Soda or Ammonia. It will be advantageous to conduct the
operation in this manner in certain cases, such for example, as when the Ore
contains substances, such as Sulphides, tellurides, arsenides and the like, that are
not readily acted upon by acids, even when employed under the influence of
Electricity.
In order that the operation may be successfully conducted it is necessary that
the metal to be dissolved should be capable of readily forming a soluble combination
with the base employed. For example, Gold, lead and antimonium, are suitable
metals to be dissolved, when the base of the Salt is Soda or Potash; and copper
silver nickel and cobalt, when ammonia is the base employed. The bath may also
be composed of solutions of soluble bases, such as potash Soda and ammonia.
The
In certain cases it is advantageous to employ ammonia, but its volatile nature.
and the odour which it emits, are serious objections to its use and render it
necessary to close the vessels containing the solution and to draw off the liquid
into other closed vessels when the electrodes require to be removed, the vapours
being drawn off by means of pumps and condensed in the usual manner.
covers of the boxes may then be removed and their contents extracted as herein-
before described. These objections to the employment of ammonia render it
generally preferable to employ carbonate of ammonia, the effect obtained being
similar but less advantageous in certain respects.
It is often advantageous as hereinafter explained to employ bases in preference
to salts and acids, because bases form with the metals somewhat unstable salts that
are very readily decomposed by electricity. The result is that with the same
electric force a much greater effect is obtained.
In applying this Invention to the treatment of Ore containing Silver alone in
the native state, it is preferable to employ a bath composed of ammonia of
carbonate of aminonia or a Sulphate or nitrate of Soda or a soluble cyanide. Seá

page_text: Salt may also be employed but in this case it is adviseable to heat the solution,
Soluble cyanide may be employed but is too expensive in practice.
When the ore contains gold or platinum alone, the bath may be composed of
Sulphates, nitrates, soluble cyanides and the like. Chloride of Sodium is to be
preferred in practice as a Salt but the best results are obtained by a bath formed of
a solution of Soda or Potash. Ores containing platinum only may be treated in
baths similar to those described for the treatment of Gold but a solution of Sea Salt
is preferable. When the ore contains two or three of these metals (gold, Silver or
Platinum) it is preferably treated in a solution of Sea Salt. The metals are
extracted simultaneously and separated by known processes.-Processes based on
the employment of electricity may also be employed for this purpose.
Ammonia, and next to ammonia, carbonate of ammonia, forms the best bath for
ore containing chloride and Sulphide of Silver. Good results may also be obtained
by employing a concentrated Solution of Chloride of Sodium at an elevated
temperature. Ore containing Sulphide of Silver is preferably treated in a bath of
ammonia.
In the case of ore containing telluride of gold, Sea Salt or cyanide of Potassium
may be employed, the telluride being placed at the positive pole. The action is
somewhat slow but the gold is obtained in the metallic state. The Ore may
constitute the negative pole, in which case, the Soda which passes to the negative
pole, acts speedily on the telluride and the gold is carried to the positive pole in
the condition of auric acid, from which pure gold may be obtained by melting with
carbon and borax.
When gold and Silver exist in the ore simultaneously with lead copper or iron,
and these metals are combined with metalloids, such as Sulphur, chloride, arsenic,
tellurium and the like or with oxygen, a heated Solution of chloride of Sodium is
employed. With a moderate current, the Gold, Silver, Copper, and lead are
collected at the negative pole and the iron falls to the bottom of the Vessel in the
condition of Oxide.
This process is accelerated by previously roasting the Ore.-The materials may
be first treated in other baths, such as a bath of Potash for the extraction of the
Gold and lead which are then separated by cupellation subsequently treating the
said materials in an ammoniacal bath to extract the Silver and Copper.
This improved process is most advantageously applied in the treatment of Ores
containing metals combined with metalloids as it enables the whole of the valuable
metal to be readily and cheaply extracted without any waste whatever. Ores of
gold, Silver and platinum usually contain a comparatively small quantity of metal
and consequently require to be mixed with conducting materials.
The precious metals being less readily dissolved by the action of the bath require
a considerable expenditure of electric power, especially when the metals are present
in the native state so that the improved process would not always be advan-
tageously applicable to the treatment of these ores commercially under these
conditions, but when the metals are combined with metalloids and water power can
be conveniently obtained. The advantages of the improved System of extraction
herein before described are very important as the cost of the mercury usually
employed with its attendant objections are entirely obviated and the metals are
completely extracted directly in the metallic state absolutely without any waste
whatever.
When the improved process is compared with the known processes, operating by
fusion, it will be observed that a considerable saving of labour plant and materials t
is also effected.
Zinc has heretofore been laboriously prepared in expensive retorts with the
consumption of a large quantity of coal and great loss from waste by volatilization
and in the form of residue. To extract zinc from calamine or carbonates, the
carbonate must be previously reduced by calcination to the condition of oxide. 5
Blende is a Sulphide of zinc usually mixed with Sulphides of iron and lead and

page_text: should be roasted carefully to bring it to the same condition as the calamine
except when lime is present.
The ore is employed as a soluble positive pole in a bath composed of alkaline
Saline or preferably of basic materials such as ammonia or carbonate of ammonia.
The zinc obtained by this process is extremely flexible and ductile. This process
also enables iron to be galvanized with zinc direct from the ore.
To extract aluminium from clay bauxite and other aluminiferous substances,"
the bath is preferably composed of a concentrated Solution of Chloride of aluminium
or double chloride of Sodium and aluminium or double chloride of aluminium and
ammonium with a powerful current of Electricity. The bath may also consist of
a concentrated solution of Soda or potash or a saturated bath of aluminate of
Soda. The intensity of the current must be considerable, otherwise the alumina
will remain at the positive pole without being decomposed.
In applying this Invention to the manufacture of magnesium, artificial carbonate
of magnesia is preferably employed, as the raw material, being obtained by
precipitating natural salts of magnesia by means of Carbonate of Soda. When
this material is employed it is placed in porous receptacles in the bath and being
dissolved without leaving any residue, the operation of removing the receptacles
for the purpose of emptying the same. of the gangue may be dispensed with.
A concentrated solution of chloride of magnesium is preferably employed as a bath
or double chloride of magnesium and Sodium or double chloride of magnesium and
ammonium.
To extract lead from its ore, a bath of marine Salt or preferably a Solution of
chloride of lead raised to nearly boiling point is employed. The lead thus obtained
is of great purity but may sometimes be slightly alloyed with zinc which admits of
being readily separated by known means. The residu contains Silver and copper
which can be extracted by means of a bath of ammonia or a Saline bath. Except
under special circumstances, for example, when a fall of water. affords a cheap
motive power this process cannot be advantageously applied to the extraction of
lead commercially on a large Scale.
This Invention may be very advantageously applied to the separation of Silver
from lead.
The argentiferous lead is melted with a small quantity of zinc and the alloy of
lead Silver and zinc which is formed at the surface during the cooling is placed
in the receptacles. of the electrical apparatus hereinbefore described. a bath of
sulphate of zinc or preferably carbonate of ammonia being employed. The zino
alone is dissolved and is deposited in a pure condition on the negative electrode.
The lead and silver are subsequently separated by cupellation. The cost of
distillation and the waste of zinc and silver which it involves are thus avoided.
Ores containing antimony are treated in a heated solution of potash or a saline
bath containing acids capable of forming soluble salts with antimony.
Mercury is obtained by treating the cinnabar in an alkaline bath or preferably
in a bath of sulphate nitrate or bichloride of mercury.
The waste by volatilisation and the noxious fumes resulting from the ordinary
treatment are entirely obviated.
Cupreous ores such as oxides and carbonates are preferably treated in an
ammoniacal or saline bath. Grey copper ores containing arsenic or antimonium
are well adapted for treatment according to this Invention and are roasted at a
low temperature without driving off the antimony and treated in a bath of potash
as hereinbefore described with reference to antimony thus obtaining this metal in
a state of great purity. The residue from the operation is treated in a bath of
ammonia or carbonnate of ammonia for the purpose of extracting the copper and
silver which are subsequently separated by known means.
Nickel is extracted from double hydrated silicates of nickel and magnesia by
first calcining the ore with carbon so as to reduce the nickel to the metallic state
and then treating it in a saline or preferably an ammoniacal bath. Ores containing

page_text: nickel alloyed with cobalt and sometimes with copper are roasted to drive off the
greater part of the sulphur and arsenic present in combination with the cobalt and
copper and treated in a bath of potash or preferably soda. The cobalt alone is
deposited on the negative electrodes in the condition of soluble cobaltate, the
residue is treated in a bath of ammonia or carbonate of ammonia to extract the
nickel and copper which may be subsequently separated by means of a bath of
sulphate of copper and a weak current which will extract the copper leaving the
nickel which may be fused or be purified by means of electricity in another
ammoniacal bath.
Ores such as are found in New Caledonia and in certain parts of the Pyrenees
are mixed with carbon and melted in a furnace to remove the greater part of the
.manganese which these ores contain. The alloy of cobalt nickel and manganese
thus obtained is firstly treated by an electric current in a sodaic bath to extract
the cobalt and subsequently in an ammoniacal bath to obtain the nickel.
In certain localities where extensive deposits of carbonate of lime and iron are
found in proximity to large falls of water available as motive power iron may be
obtained in a state of chemical purity by the employment of an electrical action in
combination with a chemical solution as hereinbefore described such as a bath of
.chloride of sodium or of iron for example.
Having now described and particularly ascertained the nature of the said
Invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is.
First A cell for recovering metals from their ores, constructed and operating
substantially as described said cell comprising a vessel containing the electrolytic
bath, a receptacle or receptacles with perforated or porous walls, immersed in
said bath and containing a conducting body of ore packel around a rod or rods
or plate or plates of non-corrodible carbonaceous material and one or more opposing
electrodes, as set forth.
Second-In the extraction of metals from their ores by means of electricity the
improvement consisting in mixing with the ore a non-corrodible conducting
material in a granular or pulverulent condition substantially as described.
Third A soluble electrode for an electrolytic cell comprising a body or mass
of granular or pulverulent ore mixed with non-corrodible conducting material
and packed around a rod or rods or plate or plates of similar material substantially
as described.
Fourth-The combination with the collecting electrodes of an electrolytic cell
of the gutters or receptacles for receiving the deposit which does not adhere to the
said electrodes substantially as described.
Fifth The combination of the containing vessel the soluble electrodes the
opposing or collecting electrodes the gutters or receptacles for receiving the deposit
which does not adhere to said collecting electrodes and the heating coil in the
bottom of said vessel substantially as described.
Sixth-The method of extracting metals by immersing the prepared materials
containing the metal in a suitable electrolytic liquid, passing a current of elec-
tricity though [sic] the said liquid from an opposing electrode to said material and
collecting the metal as oxide at said opposing electrode substantially as described.
Seventh-In combination with an electro-generator a receptacle (for conductively
prepared ore or other material containing metal to be recovered) having attach-
ments for the negative and positive polar conductors of the electro generator
arranged as described in electrical communication with the mass of conductive ore
by means of the electrolytic solution whereby reduction is effected when the current
is passed substantially as described.
Eighth-An electrolytic cell comprising one or more soluble electrodes of

page_text: conductively prepared ore packed in receptacles with perforated or porous walls
and one or more collecting electrodes and provided with an alkaline solution-as
an electrolytic bath-substantially as described.
In witness whereof I the said John Henry Johnson have to this my
Specification set my hand and seal the Seventeenth day of August One thousand
eight hundred and eighty three.
J. HENRY JOHNSON (L.S.)