IMPROVEMENTS EXTRACTING GOLD AND SILVER FROM THEIR MATRICES, AND FROM OTHER SUB- STANCES OR MATERIALS WITH WHICH THEY ARE COMBINED, MIXED, OR ASSO- OLATED
Year: 1857

page_text: IN
Westminster, Civil Engineer, for the Invention of "IMPROVEMENTS
EXTRACTING GOLD AND SILVER FROM THEIR MATRICES, AND FROM OTHER SUB-
STANCES OR MATERIALS WITH WHICH THEY ARE COMBINED, MIXED, OR ASSO-
OLATED
"
Sealed the 5th January 1858, and dated the 8th July 1857.
PROVISIONAL SPECIFICATION left by the said Joseph Gibbs at the
Office of the Commissioners of Patents, with his Petition, on the 8th
July 1857.
I, JOSEPH GIBBS, of Abingdon Street, in the City of Westminster, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE
MENTS IN EXTRACTING GOLD AND SILVER FROM THEIR MATRICES, AND FROM OTHER
SUBSTANCES OR MATERIALS WITH WHICH THEY ARE COMBINED, MIXED, OR ASSO-
CIATED," to be as follows:-
Before describing the nature of my Invention, and in order that it may be
more clearly understood, and also to define that part of the process of extracting
gold and silver from their matrix or matrices, and from the materials with
which they are commonly found combined, it is necessary to state what has
heretofore been the usual mode of extracting gold and silver, when such silver.
has been combined with gold in a common matrix.

page_text: The usual course of proceeding has been, when the object has been to
extract these metals from rock. to crush such rock, quicksilver being in con-
tact with the rock so crushed. and whilst being crushed: or to crush the rock
and wash the crushed rock, so that the metallic portions of the rock may be
separated, and then to run this separated part over a surface of quicksilver in
and thro' machines called Tyrolean mills. or otherwise to work the materials
through revolving barrels with adequate charges of quicksilver, and in the case
of gold and silver being in combination with primative gravel, or diluvial sand
of the geologists, nothing but simple washing has been commonly resorted
to, except in some cases the run of water from the washing apparatus has
had placed in or under it a surface of quicksilver contained in some vessel
over which the water glides, and on which surface of quicksilver some of the
smaller particles of clean gold are caught, and which would otherwise be lost.
From great research and numerous experiments in endeavouring to ascer-
tain the best method of extracting gold and silver. I have found that none of
these methods are adequate to the purpose of obtaining all or nearly all the
gold and silver contained in either the rock. or in the sand. or diluvial
gravels.
Now, my Invention for extracting gold and silver consists in the following
improved process. which is performed, first, in washing through sieves the
diluvial sands and gravels, so as to obtain about oth part of the original bulk
after being freed from the large stones and pebbles, which I call concentrating;
and, secondly, by regrinding or recrushing this material so concentrated. the
second crushing machine bring at the same time charged with quicksilver;
and cause the concentrated material. whether crushed or ground rock (first
concentrated), or concentrated diluvial sands or gravel to be ground tine, that it
shall, while passing and repassing, over the surface of the quicksilver. resemble
mud, and for the more perfect grinding, and to carry off the muddy substance
when so formed. I cause water to flow through the crushing machine; and,
thirdly. I sometimes smelt this concentrated material instead of grinding. as
described in the second part of my Invention; and for the more perfect opera-
tion of some of the processes described. and for maintaining the quicksilver
in a state of greater fluidity. I cause a small quantity of nitre from time to
time to be put into the second crushing machine along with the quicksilver
whilst the process is being carried on. What mean. by concentrating the
materials, is separating the small particles by washing and sifting, in the case
of diluvial soils as already described, and what I mean by concentrating in
the case of crushed rock, is separating the metallic particles by their gravities,
which is effected by washing such crushed material in the manner usually

page_text: practised in mining operations; and, further. I do not confine myself to the.
concentration of these materials to n of the original bulk, sometimes I vary
this degree of concentration: but I find from experience that generally that
degree of concentration or thereabouts is best, though I have found some
materials which are more conveniently, and may be more profitably worked
when concentrated to a less degree, sometimes when concentrated to 0 or
% of the original bulk only, after such material has been freed from all the
stone or gravel larger than one inch in diameter. The mode in which I
separate the large gravel from the small gravel or sand is performed by con-
structing a large cylinder of considerable diameter. This cylinder is covered
on its external surface with pierced plates or wire sieves, and running in
water in a cistern, which cistern receives the concentrated or small materials..
On the interior of this cylinder, strips of wood are placed parallel to its axis,
so that the gravel and sand are lifted a considerable distance. and are
repeatedly let fall into the water before they escape: by this means a con-
siderable concussion will be created by reason of the fall of the gravel upon the
water and it is by this means that the large particles are separated from the
small, so as to allow of the small passing into the cistern in which the cylinder
runs. One of the bearings of the cylinder is placed higher on the feeding
end than it is on the discharging, by which means the material is carried
forward towards the discharging end: and in order to discharge the material,
a sloping catch plate is placed in the discharging end of the cylinder above the
water surface, and over the side of the cistern. For the second grinding. I
use such crushing machines as admit of the crushers passing very slowly, so as
not to give a greater velocity to the water than about 25 revolutions per
minute, where the diameter of the grinding bason is about 30 inches, and so
on for machines where the hason is of larger diameter, the velocity of the
crushers to be proportionally reduced; but I prefer the use of a machine, as
represented in Figures 3 and 4 of the Drawings annexed, having a velocity
of about 200 feet per minute.
DESCRIPTION OF THE WASHING AND CONCENTRATING MACHINE.
This machine consists of a cylinder A revolving in the water trough A',
resting on its bearings B. B. the one being higher than the other. Figures
1 and 2, C, C. C. are a series of internal floats for elevating the sand and
gravel brought by the shoot D. Figure 1, which sand and gravel will be
elevated and again let fall several times in its passage towards the shoot E,
Figure 1, by which it will be discharged. The arms and rings F. F. F. F. are
placed some considerable distance within the cylinder to give room for these

page_text: shoots the exterior of the cylinder, as shewn at G. Figure 2. is covered with
sheets of iron plate: these plates or sheets are pierced from the inside with
small holes or iron wire, or wire sieves may be overlaid. It is not necessary that
the whole surface should be so covered, as part only may be found sufficient.
DESCRIPTION OF THE FINE GRINDING AND AMALGAMATING MACHINE.
The machine I have found by experience to effect its work in the most
efficient manner, and which causes all the gold and silver to be taken up,
consists of a pan, a section of which is shewn at Figure 3. A is the shaft for
driving the grinding balls B. B. two of a series of arms for propelling the
balls by the intervention of the propeller C. C. and the rubbing plate D. which
plate comes in contact with and pushes forward the balls E. F. F. represents
the mercury gutter, which is formed in the bottom of the pan, and which is
shewn on the plan. Figure 4. This gutter is filled with mercury up to
the ball. but not so high as materially to spread over the bottom of the pan.,
the object being not to triturate the mercury too much in the process of fine
grinding and amalgamating for I sometimes amalgamate in a separate appa-
ratus, after the second or fine grinding is completed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Gibbs in the Great Seal Patent Office on the 7th
January 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
GIBBS, of Abingdon Street, in the City of Westminster, Civil Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria. by Her Letters
Patent, bearing date the Eighth day of July, in the year of our Lord
One thousand eight hundred and fifty-seven. in the twenty-first year of Her
reign, did, for Herself. Her heirs and successors, give and grant unto me, the
said Joseph Gibbs. Her special licence that I. the said Joseph Gibbs. my
executors. administrators, and assigns. or such others as I, the said Joseph
Gibbs, 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 "IMPROVEMENTS IN EXTRACTING GOLD
AND SILVER FROM THEIR MATRICES, AND FROM OTHER SUBSTANCES OR MATERIALS
WITH WHICH THEY ARE COMBINED, MIXEL, OR ASSOCIATED," upon the condition

page_text: (amongst others) that 1. the said Joseph Gibbs, my executors or adminis-
trators, 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 1, the said Joseph Gibbs, do hereby declare the
nature of my said Invention. and in what manner the same is to be per
formed, to be particularly described and ascertained in and by the following
statement thereof. reference being had to the Drawings hereunto annexed, that
is to say:
Before describing the nature of my Invention, and in order that it may be
more clearly understood, and also to define that part of the process of extracting
gold and silver from their matrix or matrices, and from the materials with
which they are commonly found combined. it is necessary to state what has
heretofore been the usual mode of extracting gold and silver. when such silver
has been combined with gold in a common matrix.
The usual course of proceeding has been, when the object has been to
extract these metals from rock. to crush such rock, quicksilver being in con-
tact with the rock so crushed, and whilst being crushed; or to crush the rock
and wash the crushed rock. so that the metallic portions of the rock may be
separated, and then to run this separated part over a surface of quicksilver in
and through machines called Tyrolean mills, or otherwise to work the materials
through revolving barrels with adequate charges of quicksilver, and in the case
of gold and silver being in combination with primative gravel, or diluvial sand
of the geologists, nothing but simple washing has been commonly resorted
to, except in some cases the run of water from the washing apparatus has
been placed in. or under it a surface of quicksilver contained in some vessel
over which the water glides, and on which surface of quicksilver some of the
smaller particles of clean gold are caught, and which would otherwise be lost.
From great research and numerous experiments in endeavouring to ascer-
tain the best method of extracting gold and silver. I have found that none of
these methods are adequate to the purpose of obtaining all or nearly all the
gold and silver, or alloys of gold and silver contained either in the rock, or in
the sand or diluvial gravels.
Now my Invention for extracting gold and silver consists in the following
improved process, which is performed, first, in washing through sieves the
diluvial sands and gravels of the geologists, so as to obtain about 30 part of

page_text: the original bulk after such bulk has been freed from the large stones and
pebbles, which process call concentrating: and, secondly, by regrinding or
recrushing this material so concentrated, and which contains the metallic
particles. the second crushing machine being at the same time charged with
quicksilver, and I cause the concentrated material, whether crushed or ground
rock (first being concentrated). or concentrated diluvial sands or gravel. to be
ground fine, that it shall, while passing and repassing over the surface of the
quicksilver. resemble mud: and, for the more perfect grinding, and to earry off
the muddy substance when so formed. I cause water to flow through the
crushing machine; and, thirdly. I sometimes smelt or amalgamate this con-
centrated material instead of grinding as described in the second part of my
Invention and for the more perfect operation of some of the processes
described. and for maintaining the quicksilver in a state of greater fluidity. T
cause a small quantity of nitre from time to time to he put into the second
crushing machine along with the quicksilver, whilst the process is being
carried on.
What mean by concentrating the materials is separating the
small particles by washing and sifting, in the case of diluvial soils, as already
described, and what I mean by concentrating, in the case of crushed rock, is
separating the metallic particles by their gravities. which is effected by washing
such crushed material in the manner usually practised in mining operations.
And further. I do not confine myself to the concentration of these materials
too of the original bulk: sometimes vary this degree of concentration
according to the size of the metallic particles. but I find from experience, that
generally that degree of concentration or thereabouts is best, though I have
found some materials which are more conveniently and may be more profitably
worked when concentrated to a less degree. sometimes when concentrated
too or of the original bulk only, after such materials have been freed
from all the stone or gravel larger than one inch in diameter.
The mode in which separate the large gravel from the small gravel or
sand is performed by constructing a large cylinder of considerable diameter:
this cylinder is covered on its external surface with pierced plates or wire
sieves, and running in water in a cistern, which cistern receives the concen-
trated or small materials. On the interior of this cylinder, strips of wood are
placed parallel to its axis. so that the gravel and sand are lifted a considerable
distance, and are repeatedly let fall into the water before they escape. By
this means a considerable concussion will be created by reason of the fall of
the gravel upon the water, and it is by this means that the large particles are
separated from the small, so as to allow of the small passing into the cistern
in which the cylinder runs. One of the bearings of the cylinder is placed

page_text: higher on the feeding end than it is on the discharging end, by which means
the material is carried forward towards the discharging end and in order to
discharge the material. a sloping catch plate is placed in the discharging end
of the cylinder above the water surface and over the side of the cistern. and
for the second grinding. I use such crushing machines as admit of the crushers
passing very slowly. so as not to give a greater velocity to the water than
about 25 revolutions per minute where the diameter of the grinding basin is
about 30 inches, and so on for machines where the basin is of larger diameter,
the velocity of the crushers to be proportionately reduced, and prefer the
use of a machine as represented in Figures 3 and 4 of the Drawings
annexed.
DESCRIPTION OF THE WASHING AND CONCENTRATING MACHINE.
This machine consists of a cylinder resting on its hearings B. B, the one
being higher than the other. Figures 1 and 2. C. C. C. are a series of internal
floats for elevating the sand and gravel brought by the shoot D. Figure 1,
which sand and gravel will be elevated, and again let fall several times in its
passage towards the shoot E. Figure 1. by which it will be discharged The
arms and rings F. F. F. are placed some considerable distance within the
cylinder to give room for these shoots. The exterior of the cylinder (45)
shewn at G, Figure 2) is covered with sheets of iron plate: these plates or
sheets are pierced from the inside with small holes, or iron wire or wire
sieves may be overlaid. It is not necessary that the whole surface should be
so covered, as part only may be found suflicient.
DESCRIPTION OF THE FINE GRINDING AND AMALGAMATING MACHINE.
The machine I have found by experience to effect its work in the most
efficient manner. and which causes all the gold and silver, or amalgams to
be taken up, consists of a pan A. a section of which is shewn at Figure 3.
A is the shaft for driving the grinding balls; B. B. two of a series of arms for
propelling the balls by the intervention of the propeller C. C. and the rubbing
plate D, which plate comes in contact with and pushes forward the balls E, E.
F. F. represents the mercury gutter which is formed in the bottom of the pan,
and which is shewn on the plan Figure 4. This gutter is filled with mercury
up to the ball, but not so high as materially to spread over the bottom of the
pan, the object being not to triturate the mercury too much in the process of
fine grinding and amalgamating, and in some cases I amalgamate in a separate
apparatus after the second or line grinding is completed.

page_text: Having described the nature of my Invention, and the manner of carrying
the same into effect. I declare that. I do not claim any of the processes
described separately. but claim.---
First, the combined process of concentrating the metallic particles found in
ores and other substances, and then of either grinding, smelting, or regrinding
and amalgamating the same.
Second, the employment of the machine herein-before described. and repre-
sented at Figures 1 and 2 of the Drawings annexed. for separating metals
from their ores or other substances.
And, third, the combination of a mercury trough or gutter with crushing
balls, as shewn at Figures 3 and 4. in the manner and for the purposes herein-
before described.
In witness whereof. I, the said Joseph Gibbs. have hereunto set my hand
and seal, this Thirteenth day of October. One thousand eight hundred
and fifty-seven.
JOSEPH GIBBS. (L.S.)