IMPROVE- MENTS IN THE TREATMENT OF COPPER ORES, AND IN APPARATUS FOR THE SAME
Year: 1862

page_text: LETTERS PATENT to William Clark, of 53, Chancery Lane, in the County
of Middlesex, Engineer and Patent Agent, for the Invention of " IMPROVE-
MENTS IN THE TREATMENT OF COPPER ORES, AND IN APPARATUS FOR THE
SAME." A communication from abroad by Mr. Frédéric Le Clerc, Doctor
Sealed the 21st April 1863, and dated the 29th October 1862.
PROVISIONAL SPECIFICATION left by the said William Clark at the
Office of the Commissioners of Patents, with his Petition, on the 29th
October 1862.
I, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE TREATMENT OF COPPER ORES, AND IN APPARATUS FOR
THE SAME," to be as follows:-
This Invention relates to the treatment of copper ores, and more particularly
those of grey copper. First I obtain a white matt in the same manner as in
ordinary; the matt is then broken into large fragments and subjected to a
complete roasting in a reverberatory furnace, in which air is supplied through
several openings. Immediately a red heat is obtained, I project air over the

page_text: surface of the heated matt, or to proceed more rapidly, I blow the air into the
metallic bath immediately it is obtained. The action of the air is continued
until vapours cease to disengage, taking the precaution to agitate and stir up
the bath in such manner as to bring the greatest possible amount of the metal
in contact with the air. After operating for a few hours in this manner I
obtain a malleable copper, but still containing large quantities of arsenic and
antimony.
Theory-Copper ore which is one of the most difficult to treat, and on
which I have made particular experiments gives on analysis the following
average, viz. :-
Copper
Iron
Sulphur
Arsenic
Antimony
Sulphate of baryta
Carbonated iron
17 parts,
7 parts,
5 parts,
6 parts,
25 parts,
27 parts,
-
12 parts,
Total 99 parts.
Under the influence of air at a certain temperature the arsenic and antimony
become oxidized and disengage in white fumes in a state of arsenious acid and
antimonious acid. The iron which has lost its carbonic acid unites with the
silicate of alumina of the iron and forms silicate of alumina and iron, one part
of the copper passes into a state of protoxide, and aids in the transformation of
the iron into silicate, it also acts as a powerful agent for the decomposition
of sulphurets. Under its influence it produces sulphurous acid and the copper
passes into a metallic state. The operation will be terminated or about to
terminate on the matters commencing to bubble with considerable noise, which
is caused by the sulphurous acid becoming disengaged. In order to reduce the
small quantity of silicate of copper which forms, it is of advantage before giving
the last stir to the furnace, and before tapping the contents, to add a
little charcoal to the metallic bath which I stir up and allow to act for some
minutes.
2ndly, I
may also in some cases extract the copper at once without having
recourse as before to the formation of a matt. It is only necessary to roast
the fragments of copper ore in a brisk fire and submit it to the action of air as 3
before described.
3rdly, the copper ore although malleable still retains traces of arsenic and

page_text: antimony. In order to render it suitable for commercial uses I melt it in a
reverberatory furnace, and when fusion is complete I submit the metal bath
to the action of steam. Several methods may be adopted for effecting the above
purpose, but the most practical one is as follows:-An ordinary reverberatory
furnace is divided into two compartments, in one of which, nearest the chimney,
the copper is fused; in order to increase the heat, in addition to the ordinary heat
of the furnace, the sole may be heated by a supplementary furnace placed
underneath. Immediately fusion is effected, I open a passage for the metallic
bath, which then runs into the other compartment next to it. The sole of this
compartment is much deeper than that of the one where the metal is melted,
its depth being regulated by the amount of the metallic bath it receives. The
steam is introduced a little in front of the running off orifice by means of orifices
situated laterally on a level with the bottom of the sole. These orifices
which vary in diameter according to the volume and extent of the metallic
bath, are hollowed out of tubes of refractory clay in direct communication with
a cast-iron reservoir containing the steam. This steam should be at a high
temperature and superheated in order to prevent the metal bath from cooling
and consequently from concretion. This steam may also be injected into the
bath from above. In this arrangement the cast-iron reservoir receiving the
steam should be placed in the reverberatory furnace itself, and there submitted
to a high temperature, hence a superheating apparatus is unnecessary. The
lower face of this reservoir is furnished with tubes of refractory clay as above
mentioned, which tubes dip into the bath to the required depth. A large
tube of refractory clay suitably supplied with holes, or a wheel similar to.
hydraulic wheels, or a kind of turbine of refractory clay, may be applied in order.
to suitably agitate the steam in the metallic bath.
Lastly, the steam may also be projected into the bath from beneath, in which.
case the reservoir containing the steam is placed on the sole,, but this arrange-
ment is difficult of execution.
Theory. The metallic bath may contain iron, sulphur, lead, zinc, tin, or other
matters, but it contains with certainty both arsenic and antimony. The steam.
becoming decomposed the oxygen acts on the above indicated substances, the
former of which forms oxides and consequently silicates of alumina under the
influence of the silica on the side of the furnace. The sulphur, arsenic, and
antimony combine with the nascent hydrogen and are volatilized.
Note. It is well to plunge a wooden rod into the metallic bath to destroy
the arseniates and antimoniates which may form.
4thly, the white matt itself may be submitted with success to the foregoing

page_text: treatment under the third] head, but in this case the steam should act
for a much more considerable time than when treating copper in a metallic
state.
5thly, the action of air on the one part, and of steam on the other part
permits of refining copper used in commerce, such as Chili copper, North and
South American copper, English and other copper, I can apply the above
agents for refining copper at any suitable time and place.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Clark in the Great Seal Patent Office on the 29th
April 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of October, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Clark, Her special licence that I, the said William Clark, my
executors, administrators, and assigns, or such others as I, the said William
Clark, my executors, administrators, and 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 "IMPROVE-
MENTS IN THE TREATMENT OF COPPER ORES, AND IN APPARATUS FOR THE SAME," a
communication to me from abroad by Mr. Frédéric Le Clerc, Doctor of
Medicine, of 29, Boulevart St. Martin, Paris, upon the condition (amongst
others) that I, the said William Clark, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Invention,
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 William Clark, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed

page_text: to be particularly described and ascertained in and by the following statement
(that is to say):
:
This Invention relates to the treatment of copper ores, and more par-
ticularly those of grey copper. 1st, I obtain the matt in the same manner
as in ordinary. The matt is then broken into large fragments, and sub-
jected to a complete roasting in a reverberatory furnace, in which air is
supplied through several openings. Immediately red heat is obtained I
project air over the surface of the heated matt, or I may blow the air into
the metallic bath or melted metal immediately it is obtained. The action of
the air is continued until vapours cease to disengage, taking the precaution to
agitate and stir up the bath in such manner as to bring the greatest amount
of the metal in contact with the air. After operating for a few hours in this
manner I obtain a malleable copper, but still containing large quantities of
arsenic and antimony.
Theory. The following description of the treatment of white matt will
also apply to any other matt obtained from copper ore. Under the influence of
air, and at a certain temperature, the arsenic and antimony become oxydized
and disengage in white fumes in a state of arsenious acid and antimonious
acid, the sulphur in combustion is changed into sulphurous acid. The iron
also unites with the silicate of alumina on the sides of the furnace, and forms.
silicate of alumina and iron, one part of the copper passes into a state of
protoxide and assists in the transformation of the iron into silicate; it also
acts as a powerful agent for the decomposition of sulphurets. Under its
influence it produces sulphurous acid and copper while the sulphuret of copper
passes into a metallic state. The operation will be terminated or about to
terminate on the matters commencing to bubble with considerable noise, which
is caused by the sulphurous acid becoming disengaged. In order to reduce
the small quantity of silicate of copper which forms, it is of advantage before
giving the last stir to the furnace, and before tapping the contents, to add a
little charcoal to the metallic bath, which I stir up and allow to act for some
minutes.
Refining. I may also obtain copper in a state fit for use by treating in the
following manner :-Any kind of copper will serve while still impure, and
especially that extracted from grey copper ores by the means herein-after
described, and without the addition of iron or copper pyrites.
1st, by blowing hot air into the interior of the metallic bath.
2ndly, by passing a current of steam into said bath.
3rdly, by placing charcoal or coke in powder in the bath, and agitating

page_text: stirring up, and mixing the whole intimately together. This action, if repeated
two or three times, is sufficient to produce copper of remarkable purity, and
which may be brought to a state of chemical purity by rendering the operation
continuous.
Theory. Supposing it is desired to refine copper containing arsenic and
antimony, which is ordinarily the case, as almost all kinds of copper con-
taining traces of these two substances. Copper contains arsenic and antimony
in a metallic state, that is, as an alloy; it also contains arseniate and
especially antimoniate of copper.
The metallic bath is thus formed of a com-
paratively large quantity of copper and small proportions of metallic arsenic
and antimony, which are so intimately combined with the copper as to prevent
their extraction by the ordinary processes from the mass of copper being so
largely superabundant as compared with the small amount of the two other
metals. The bath also contains in addition arseniate and antimoniate of
copper. The subsequent addition to the metallic bath of the charcoal in
powder, and its intimate combination therewith, decomposes the componate
parts, as the iron rod serving to stir up the mass on being withdrawn from
the bath gives off abundant quantities of white vapours of arsenious and
antimonious. acids on coming in contact with the air. Silicate of alumina also
forms on the sides of the furnace, together with other injurious substances.
The silicate is more or less charged with silicate of copper, which may be
afterwards reduced by means of the charcoal. The current of steam pro-
jected into the bath serves as an agitator, and also for separating the oxygen
from the hydrogen, which thus assists in separating the copper from the
arsenic and antimony.
Having described the nature of this Invention and the manner of per-
forming the same, I declare that what I claim as the Invention to be protected
by the herein-before in part recited Letters Patent is,―
First, the method of extracting metallic copper direct from any kind of
matt by the simple action of air projected on the matt while at a red heat, or
by injecting air into the matt in a state of fusion, and apparatus applied as
and for the purposes herein described.
Secondly, I claim refining all kinds of copper while in an impure state by
the injection of air into the interior of the metallic bath; also by the admis-
sion of steam into said bath, and intimately mixing charcoal or coke in powder
therewith.
.
Thirdly, I claim the method of extracting metallic copper from ores con-
taining copper pyrites and from grey copper ores by treating said ores in a

page_text: blast furnace with carbon and with the action of air injected, as in ordinary
blast furnaces, or with steam injected, all as herein-before described.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this Twenty-ninth day of April, in the year of our
Lord One thousand eight hundred and sixty-three.
Witness,
JAMES DAISH,
53, Chancery Lane,
London.
W. CLARK. (L.S.)