Improvements relating to the Extraction of Metals from Refractory, Complex, and other Ores.
Year: 1888

page_text: Date of Application, 10th Jan., 1888.
Complete Specification Left, 18th June, 1888.
Complete Specification Accepted, 24th Aug,
1888
PROVISIONAL SPECIFICATION.
Improvements relating to the Extraction of Metals from Refractory,
Complex, and other Ores.
We, HENRY RYAN LEWIS, of Bartholomew House, Bank, in the City of London,
Mining Engineer and Metallurgist, and CHARLES BERRY PHILLIPS, of Hoole Cottage,
Chester, in the County of Chester, Gentleman do hereby declaro the nature of this
invention to be as follows:-
Our invention relates to the extraction of gold and silver from auriferous and
argentiferous ores, and comprises an improved method or process which. is
more especially advantageous for the treatinent of refractory or rebellious and
complex ores.
By our invention we provide for the reduction of the said ores and the extraction
of the precious metals therefrom by means of a blast-furnace of the kind or class
And we can use either existing or
generally used in the production of pig-iron.
specially constructed furnaces of this kind for the treatment of ores according to our
said invention.
We sometimes effect the extraction of the precious metal simultaneously with tho
manufacture of pig-iron or of alloys such as Ferro-manganese, Spiegeleisen, Chrome-
iron or Tungsten-iron.
33
"Water-Jacket smelting furnaces
Blast-furnaces of the kind or class known as
have, in some instances, been used for the reduction of ores containing gold or
silver; but such furnaces are not adapted for the production of pig-iron, and
their capacity is very small as compared with the blast-furnaces which we employ ;
moreover the process of treating the ores differs materially from our improved
process.
In treating the auriferous or argentiferous ores in a blast-furnace, according to our
said invention, suitable proportions of lead, or of ore containing lead, and of
manganiferous or other iron or manganese. ore, or a combination of these ores, or

page_text: pig-iron, scrap-iron or the like must be mixed with the auriferous or argentiferous
ores, or introduced therewith into the furnace. Refractory gold and silver ores
generally contain more or less sulphur, arsenic, zine, antimony or other substances,
which, if not carried away or expelled from the ores during the roasting thereof in
the upper portion of the furnace, would cause the formation of a pasty mass, so that
the furnace would "hang" and the result of the process would thus be depreciated.
In our process, however, these substances, being reduced if necessary to the metallic
state in the upper portion of the furnace, are volatilized by the heat and deposited in
the flues or chambers of the furnace as flue-dust; or as oxides of these metals or
elementary substances. Should it be considered expedient to utilize the waste heat
or gases from the furnace, these products will be saved in the manner above described.
If, however, it is not necessary or desirable to utilize the waste heat of the gases,
these products may be either saved in flues or chambers or permitted to escape at
once into the atmosphere. If the auriferous and argentiferous ores contain a
considerable proportion of sulphur, arsenic, antimony, bismuth or the like, it is
advisable to roast these ores previously to treatment in the blast-furnace; and it may
be advantageous to roast them with common salt (chloride of sodium), converting
them into oxides and chlorides, because large quantities of sulphides or sulphurets
are detrimental to the free working of the furnace, whereas oxides and chlorides are
more readily dealt with therein. The roasting of the ores can, if desired, be effected
by means of the waste gases from the blast-furnace.
As a means of increasing the heat of the furnace if necessary, or should it be
found that the furnace hangs, we introduce into the furnace through the buyeres a jet
or jets of liquid hydrocarbon such as, for instance, crude or refined petroleum,
which together with the air-blast produces an intense heat and thus overcomes any
disposition of the burden to hang or become pasty, and ensures the successful working
of the furnace.
On the proportion of manganese and iron or manganiferous ores used with the
auriferous or argentiferous ores (either native or prepared as above described)
in the blast-furnace will depend the successful formation of a fusible slag and
the successful reduction and extraction of the various metals hereinafter mentioned.
When the extraction of the precious metals is to be effected simultaneously with
the production of pig iron or any alloy of iron, it may not always be necessary to
introduce into the furnace oxide of manganese or oxide of iron, other than
that present in the ore from which the pig-iron or alloy of iron is to be made, the
mixture or burden depending on the analyses of the different ores to be treated.
Moreover when the auriferous or argentiferous ores contain a sufficient quantity of lead
for the purpose hereinafter specified, it is unnecessary to add to the charge any further
quantity of lead or of ore containing lead.
The ores together with any iron or lead that may be required, the fuel and the
requisite flux or fluxes are charged into the blast-furnace, which is worked with either
hot or cold blast.
The burden is made up of certain proportions of the different ores and fluxes
according to the various analyses thereof, and such proportions should be maintained
or altered according to the analysis of the ores under treatment from time to time
while the blast-furnace is in operation. For instance, assuming that an auriferous and
argentiferous ore, as taken from the mine (without any dressing or washing), contains
say about
60 per cent. of silica.

page_text: an anoy or
"matte"
12 OZS. of Gold
500 ozs. of silver
2 tons of Lead.
With these three examples we illustrate the method of mixing the ores already alluded
to, but, according to the various classes of ores to be treated, the burden can be
modified so as always to ensure the free working of the furnace and we deem it
preferable to mix several of the different ores, thus probably making it easier to
obtain the necessary proportions, as one ore may contain ingredients which another
ore requires, and so the ores will assist each other in the reduction.
After reduction, the melted metals collect in the hearth or crucible of the blast-
furnace, the lead forms an alloy with the gold or silver, or both, and settles at the
bottom of the hearth or crucible, whilst the molten iron or its alloy, being of less
specific gravity, floats upon the surface of the said lead alloy and forms a protecting
layer above the same, which prevents oxidation thereof. Such other ingredients of
the ores as are incapable of volatilization at the temperature employed, together with
the flux or fluxes, form a fusible slag, which is drawn off in the ordinary manner.
The molten iron is periodically drawn off by means of a tap-hole provided at a suitable
level for the purpose; the lead alloy is periodically drawn off by means of a tap-hole
at, or near, the bottom of the hearth or crucible.
Care must be taken to have the tap-hole for the iron a sufficient height above the
bottom of the hearth or crucible to ensure that the level of the lead alloy shall not rise
above the said tap-hole. Care must also be taken, when drawing off the said alloy
from the bottom tap-hole, that this tap-hole is élosed before the level of the said alloy
has descended sufficiently to permit the escape of any of the iron therewith.
In order that the method of drawing off the various products may be clearly under-
stood, we would observe that provision, in the first place, should be made in the usual
manner for drawing off and disposing of the slag. At stated and regular intervals,
the upper tap-hole should be opened, and the iron or its alloy drawn off to the level
thereof, the said tap-hole being afterwards made up; then, if the alloy of lead with the
precious metals is estimated to be in sufficient quantity to necessitate the drawing-off
of the same, the lower tap-hole should be opened and kept open until the said alloy is
drawn off this tap-hole should be stopped and made up before any iron or alloys of
iron remaining below the upper tap-hole and above the upper surface of the lead
alloy commences to run. The furnace is then cleaned, if necessary, and made ready
for repeating the operation. During the tapping, the blast may require to be.
shut off.
In treating refractory or complex ores according to our said invention, the said
ores, previous to being charged into the blast-furnace, are calcined, if deemed
necessary, to drive off any excess of sulphur, arsenic, or other substance capable of
volatilization which may be present in the ores.
or suitable calcining furnace or kiln may be employed, and, if desired, the waste
For this purpose, any well-known
gases may be used as above stated.
To prevent loss by percolation of the lead alloys through the joints of the brick-
work of the hearth or crucible of the blast-furnace, this part of the furnace must
be built completely tight.
We prefer that the crucible-should be moulded or otherwise made from one piece
or block of refractory material, such as Stourbridge fire-clay organister, and that
the apparatus should be constructed as follows, that is to say:-The crucible is built

page_text: or placed upon and fitted into a stone foundation and surrounded by an outside
casing of fire-bricks or blocks so that the weight of the furnace or its interior lining
may not all rest on the crucible, but be distributed on both the casing of the crucible
and the crucible, thus ensuring that no undue pressure shall be thrown on the sides
of the crucible; a packing of ground ganister or fire-clay may be rammed in between
the crucible and the fire-brick casing and also under the crucible, so that, in case of
fracture or leakage of the crucible, the molten metals will not escape; the outside
casing of fire-bricks or blocks may be surrounded by an iron casing water-cooled or
not, and the stone base or foundation may rest on an iron plate; this plate may be
supported above the level of the ground on short columns of masonry or iron, thus
preventing any leakage into the ground of the molten metals should any accident
occur to the crucible and the stone foundation, as these metals would be of great value
and we purpose that all necessary precaution should be taken so that no loss may
occur.
The gold, silver, and any other metals that may be alloyed with the lead drawn
from the crucible are separated from the lead and from each other by any well-known
or suitable method or process.
In some instances, the metals or other substances volatilized during the process are
obtained as bye-products by condensation of the vapours evolved in flues or chambers
specially provided and prepared for the purpose. In other instances, the said vapours
are permitted to escape into the atmosphere.
Among the ores that may be treated by our improved process are the following
viz., gold, silver lead, platinum, cobalt, tin, antimony, zinc, chromium tungsten,
manganese, iron, copper, bismuth, nickle, and any of the rarer metals, auriferous and
argentiferous copper and iron pyrites or auriferous and argentiferous arsenical pyrites,
or tellurides, when these contain gold or silver, also cupreous gold and silver ores,.and
the ores obtained from Anglesea and elsewhere and known as Bluestone."
T
1000
"
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements relating to the Extraction of Metals from Refractory,
Complex, and other Ores.
We, HENRY RYAN LEWIS, of Bartholomew House, Bank, in the City of London,
Mining Engineer and Metallurgist, and CHARLES BERRY PHILLIPS, of Hoole Cottage,
Chester, in the County of Chester, Gentleman, 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:-
Our invention relates to the extraction of gold and silver from auriferous and
argentiferous ores, and comprises an improved method or process which is more
especially advantageous for the treatment of refractory or rebellious and complex
ores.
By our invention, we provide for the reduction of the said ores and the extraction
of the precious metals therefrom by means of a blast-furnace of the kind or class
generally used in the production of pig-iron. And we can use either existing or
specially constructed furnaces of this kind for the treatment of ores according to our
said invention.
We sometimes effect the extraction of the precious metal or metals simultaneously
with the manufacture of pig-iron, or of alloys such as Ferro-manganese, Spiegeleisen,
Chrome iron or Tungsten-iron.
Blast-furnaces of the kind or class known as "
Water-Jacket smelting furnaces"
have, in some instances, been used for the reduction of ores containing gold or silver;
but such furnaces are not adapted for the production of pig-iron, and their capacity is
very small as compared with the blast-furnaces which we employ; moreover the
process of treating the ores differs materially from our improved process.
In treating the auriferous or argentiferous ores in a blast-furnace, according to our
said invention, suitable proportions of lead, or of ore containing lead, and of
manganiferous or other iron ore, manganese ore, or a combination of these ores, are
mixed with the auriferous or argentiferous ores, or introduced therewith into the
furnace.
Refractory gold and silver ores generally contain more or less sulphur, arsenic,
zinc, antimony or other substances, which, if not carried away or expelled from the
ores during the roasting thereof in the upper portion. of the furnace, would cause
the formation of a pasty mass, so that the furnace would "bang" and the result of the
process would thus be depreciated. In our process; however, these substances, being
reduced if necessary to the metallic state in the upper portion of the furnace, are
volatilized by the heat and deposited in the flues or chambers of the furnace as flue-
dust, or as oxides of these metals or elementary substances. Should it be considered
expedient to utilize the waste heat or gases from the furnace, these products will be
saved in the manner above described. If, however, it is not necessary or desirable to
utilize the waste heat of the gases, these products may be either saved in flues or
chambers or permitted to escape at once into the atmosphere. If the auriferous and

page_text: argentiferous ores contain a considerable proportion of sulphur, arsenic, antimony,
bismuth or the like, it is advisable to roast these ores previous to their treatment in
the blast-furnace; and it may be advantageous to roast them with common salt
(chloride of sodium), converting them into oxides and chlorides, because large
quantities of sulphides or sulphurets are detrimental to the free working of the
furnace, whereas oxides and chlorides are more readily dealt with therein. The
roasting of the ores can, if desired, be effected by means of the waste gases from
the blast-furnace.
As a means of increasing the heat of the furnace if necessary, or should it be found
that the furnace hangs, we introduce into the furnace through the tuyeres a jet or jets
of liquid hydrocarbon, such as crude or refined petroleum, which, together with the
air-blast, produces an intense heat and thus overcomes any disposition of the burden
to hang or become pasty, and ensures the successful working of the furnace.
On the proportion of manganese and iron or manganiferous ores used with the
auriferous or argentiferous ores (either native or prepared as above described) in the
blast-furnace will depend the successful formation of a fusible slag and the successful
reduction and extraction of the various metals hereinafter mentioned.
When the extraction of the precious metals is to be effected simultaneously with the
production of pig iron or an alloy of iron, it may not always be necessary to introduce
into the furnace oxide of manganese or oxide of iron, other than that present in the
ore from which the pig-iron or alloy of iron is to be made, the mixture or burden
depending on the analyses of the different ores to be treated. Moreover, when the
auriferous or argentiferous ores contain a sufficient quantity of lead for the purpose
hereinafter specified, it is unnecessary to add to the charge any further quantity of
lead or of ore containing lead.
The ores together with any iron or lead that may be required, the fuel and the
requisite flux or fluxes are charged into the blast-furnace, which is worked with either
hot or cold blast.
The burden is made up of certain proportions of the different ores and fluxes
according to the various analyses thereof, and such proportions should be maintained
or altered according to the analysis of the ores under treatment from time to time
whilst the blast-furnace is in operation.
For instance, assuming that we are treating an auriferous and argentiferous oro as
taken direct from the mine (without any dressing or washing) the analysis of which is

page_text: Before treating this class of ore in the blast-furnace, it is desirable, on account of
the large percentage of Sulphur contained therein, to first calcine the ore and then to
arrange the furnace-burden in such proportions as will work to advantage with the
iron, manganese or manganiferous iron ores that are to be used with it.
example of the burden to be used we give the following
As an
Say 10 cwt. of 50 per cent. Iron ore.
this we reckon at about 35 per cent. riclier
5 wt. of 50 per cent. manganese ore.
5 cwt. of the calined Bluestone
in metals than the raw ore.
5 cwt. of Lime or other flux.
25 cwt. of Fuel.
The result of treating 100 tons of iron ore, 50 tons of manganese ore and 50 tons
of the calcined Bluestone, will be about from 65 to 70 tons of Ferro-manganese, Zinc
Oxide equal to about 45 tons of metallic Zine; and an alloy or matte containing
about 7 tons of Lead. 800 oz. of Silver, 1.7 ozs. of Gold and 2 tons of copper.
By the examples above given we illustrate the method of mixing the ores already
alluded to the burden should, however, be modified according to the class of ores to
be treated, so as always to ensure the free working of the furnace and we deem it
preferable to inix several of the different ores, thus probably making it easier to obtain
the necessary proportions, as one ore may contain ingredients which another ore
requires, and so the ores will assist each other in the reduction.
In giving the foregoing examples we have stated the proportions of the various
ores, fluxes and fuel that we consider would be advisable to use, so that the produce
of either the iron, Ferro-manganese, Spiegeleisen or other substances will be of a
merchantable value; in practice, however, and according to the heat of the blast and
the quantity and quality of the fuel employed, it may be judicious to alter the propor-
tions of the burden in favor of the ores containing the precious metals, or the reverse;
should this not be considered essential to the successful working of the process, the
burden can be otherwise altered in such manner and proportions as may be deemed
advisable, so as to ensure the free working of the furnace. The percentage of loss
of the baser metals will generally be influenced by the temperature of the blast, the
quality and quantity of the fuel, the heat at which the furnace is working and the
description of slag running.
After reduction the melted metals collect in the hearth or crucible of the blast
furnace, the lead forms an alloy with the gold, or silver, or both, and the copper (if
any) and settles at the bottom of the hearth or crucible, whilst the molten iron, or its
alloy, being of less specific gravity floats upon the surface of the said lead alloy and
forms a protecting layer above the same, which prevents oxidation thereof. Such
other ingredients of the ores as are incapable of volatilization at the temperature
employed, together with the flux or fluxes, form a fusible slag, which is drawn off in
the ordinary manner. The molten iron is periodically drawn off by means of a tap-
hole provided at a suitable level for the purpose; the lead alloy is periodically drawn
off by means of a tap-hole provided for the purpose at, or near the bottom of the
hearth or crucible.
Care must be taken to have the tap-hole for the iron a sufficient height above the
bottom of the hearth or crucible to ensure that the level of the lead alloy shall not
rise above the said tap-hole. Care must also be taken, when drawing off the said alloy
from the bottom tap-hole, that this tap-hole is closed before the level of the said alloy
has descended sufficiently to permit the escape of any of the iron therewith.
In order that the method of drawing off the various products may be clearly under-
stood, we would observe that provision, in the first place, should be made in the usual
manner for drawing off and disposing of the slag. At stated and regular intervals,
the upper tap-hole should be opened, and the iron or its alloy drawn off to the level
thereof, the said tap-hole being afterwards made up; then, if the alloy of lead with
the precious metals is estimated to be in sufficient quantity to necessitate the drawing

page_text: off of the same, the lower tap-hole should be opened and kept open until the said
alloy is drawn off; this tap-hole should be stopped and made up before any iron or
alloy of iron remaining below the upper tap-hole and above the upper surface of the
lead alloy commences to run. The furnace is then cleaned, if necessary, and made
ready for repeating the operation. During the tapping, the blast may require to be
shut off.
In treating refractory or complex ores according to our said invention, the said ores,
previous to being charged into the blast-furnace, are calcined, if deemed necessary,
to drive off any excess of sulphur, arsenic, or other substance capable of volatilization
which may be present in the ores. For this purpose, any well-known or suitable
calcining furnace or kiln may be employed, and, if desired, the waste gases may be
used as above stated.
To prevent loss by percolation of the lead alloys through the joints of the brick-
work of the hearth or crucible of the blast-furnace, this part of the furnace must be
built completely tight.
We prefer that the crucible should be moulded or otherwise made from one piece or
block of refractory material, such as Stourbridge fire-clay, or ganister, and that
the furnace should be constructed as illustrated in the accompanying drawings,
in which
Figure 1 is a vertical central section illustrating one form of our improved
furnace, and
Figure 2 is a similar view showing another form or modification thereof:
Like letters indicate corresponding parts in these Figures.
A is the solid hearth crucible of Stourbridge fire-clay or other suitable material.
This crucible, in the furnace shown in Figure 1, is built or placed upon, or fitted into
a stone foundation B, and is surrounded by an outer casing C of fire bricks or blocks,
so that the weight of the furnace or its interior lining will not rest wholly on the
crucible, but will be distributed over the said casing C and the crucible, thus ensuring
that no undue pressure shall be thrown on the sides of the crucible. Ground ganister
or fire-clay is preferably rammed in to serve as packing between the crucible and
the fire-brick casing and also under the crucible as at D, so that, in case of fracture
or leakage of the crucible, the molten metals will not escape. The outer casing C is,
if desired, surrounded by an iron casing which may or may not be water-cooled.
The stone base or foundation B is preferably placed upon an iron plate E supported
above the level of the ground on short columns F of metal or masonry.
provide for preventing any leakage into the ground of the molten metals should any
accident occur to the crucible and the stone foundation. As the metals are of great
value, it is very desirable that all necessary precaution should be taken to prevent loss
thereof.
We thus
G is the slag-hole or tap-hole for the slag. H is the tap-hole for the iron, and I is
the tap-hole through which the auriferous, or argentiferous lead is to be drawn off.
KK are the tuyeres. L. L are pillars or columns resting upon a foundation L' and
supporting at their upper ends an annular plate or entablature M of iron or other
metal. N indicates the boshes and inner lining of the furnace. O is a lining or
5 casing of fire-brick and P is an outer metal casing, both of which rest upon the plate
or ring M. Qis an opening for permitting the cleaning of the furnace. This opening
is closed by means of a plate or stone door, from the aperture G in which the slag
can be drawn.
In the apparatus shown in Figure 2, we dispense with the brick casing, the stone
O foundation and the packing shown in Figure I and we place the crucible directly upon
the iron plate E. The crucible is encased with iron as at R and may be jacketted
and water-cooled if necessary.
The crucible in this form of construction can be
readily removed and replaced, the columns L, the entablature M and the iron
casing Psupporting the entire weight of the furnace from the tuyeres upwards.
The gold, silver, and any other metals that may be alloyed with the lead drawn
from the crucible are separated from the lead and from each other by any well-known
or suitable method or process.

page_text: In some instances, the metals or other substances volatilized during the process are
obtained as bye-products by condensation of the vapors evolved, in Hues or chambers
specially provided and prepared for the purpose. In other instances, the said vapors
are permitted to escape into the atmosphere.
Among the ores that may be treated by our improved process are the following,
viz. gold, silver, lead, platinum, cobalt, tin, antimony, zinc, chromium, tungsten,
manganese, iron, copper, bismuth, nickel and any of the rarer metals, auriferous and
argentiferous copper and iron pyrites, or auriferous and argentiferous arsenical pyrites,
or tellurides, when these contain gold or silver, also cupreous gold and silver
ores, and the ores obtained from Anglesea and elsewhere and known as Bluestone.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we wish it understood that
we claim
-
First. The extraction of the gold and silver or either metal from auriferous or
argentiferous ores, with or without the simultaneous production of pig-iron or alloys
of iron, by reducing such ores in a blast-furnace together with manganese or manga-
niferous ores and iron and lead or orcs containing the same or either of them in the
requisite proportions, with suitable fluxes substantially as above described, having
regard to the amount of manganese, iron and lead already present in the ores to be
treated.
Second. In the above described process, the simultaneous production of pig-iron
and auriferous or argentiferous lead by the employment of a blast-furnace constructed
substantially as described.
Third. The employment, in the above described process of treating argentiferous
and auriferous ores, of a furnace constructed with a solid hearth crucible and with
several tap-holes used at various levels in the manner, and for the purposes, substan-
tially as described.
Dated this 16th day of June 1888.
HENRY RYAN LEWIS.
CHARLES BERRY PHILLIPS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.