Improved Method and Machinery or Apparatus for Extracting Gold from Crushed Ore or Material Containing it.
Year: 1896

page_text: Date of Application, 30th May, 1896
Complete Specification Left, 1st Mar., 1897-Accepted, 29th May, 1897
Improved Method and Machinery or Apparatus for Extracting Gold
from Crushed Ore or Material Containing it.
I, ARTHUR SAMUEL FRANCIS ROBINSON, of the Vale of White Horse Iron
Works, Wantage, in the County of Berks, Engineer, do hereby declare the nature
of this invention to be as follows:-
According to my invention for the purpose of extracting gold from finely divided
gold bearing material the material to be treated (hereinafter referred to as crushed
ore) is mechanically divided into small streams, then fed by gravity onto a wetted
amalgamated travelling surface which retains a part of the material so fed to it,
carrying the same a certain distance, then the sprinkled travelling amalgamated
surface has projected against it a strong current or currents of air free from solid
matter, and thereafter the surface so treated is passed through water. By this
method I am enabled to obviate disadvantages which I have found to result in
practice when blasting an amalgamated plate with mixed air and ore whereof a
portion is liable to rebound and carry metal down into the trough of the apparatus
besides which a considerable amount of floating dust is given off which in some
cases would contain "float gold." Machinery or apparatus for carrying the above
method of extracting gold into effect may be constructed in various forms.
According to one arrangement the travelling amalgamated surface is that of a
drum dipping more or less at the under side into water in a suitable trough and on
to a watered portion of which surface is or are dropped a fine thin stream or streams
of pulverized cre at such a point that the drum being suitably large and driven
slowly a considerable period elapses between the delivery of the ore to the drum
and re-entry of the so sprinkled surface into the water and consequent washing off
of some of the finely divided material, preparatory to which a strong blast (or
blasts) of air unmixed with solid particles is projected against the sprinkled surface
so as to force any amalgamated portions into contact with the mercury and ensure
their retention. Although water is used, a comparatively very small quantity will
suffice, and it is not necessary to have a running stream. As the mud collects in
the bottom of the trough it can be drawn off and allowed to settle in a tank whence
the water can be used over and over again.
I sometimes construct an apparatus with two or more troughs each with a drum
having an amalgamated surface on to which the material to be treated is fed by
gravity at one point in the rotation of the drum whilst subsequently the surface so
sprinkled is subjected to a blast or blasts of air alone. According to one arrange-
ment constructed with two or more troughs and drums one trough is arranged to
overflow into another either from above or below, the feed is adapted to feed two
or more drums all or some only of which are subjected to an air blast after the
deposit on the respective amalgamated surface of material to be treated. In such
an arrangement floating particles of gold could be floated over from the trough of
the first drum on to the second drum and again treated and so on.
According to another construction, adapted to treat in a continuous manner all
sludge settling in the trough of the primary drum over and over again there are
several troughs, say three, for example, each provided with an amalgamated drum,
the first or primary drum having the material to be treated dropped on to it, and
being subjected to an air blast, the matter deposited in its trough being delivered
onto the second drum, which is also subjected to an air blast, the matter deposited

page_text: into the second trough being delivered onto the third drum, which is or may be also
subjected to an air blast and the deposit from the third trough being delivered
into a settling tank whence the water is returned to the first trough for re-use and
Bo on.
The contents of the troughs being heavy, mechanical means of any suitable kind
such as a travelling set of paddles a screw or some equivalent might if found
desirable be provided to deliver the matter from the first and second troughs
respectively on to second and third drums.
Dated this 30th day of May 1896.
Improved Method and Machinery or Apparatus for Extracting Gold
from Crushed Ore or Material Containing it.
I, ARTHUR SAMUEL FRANCIS ROBINSON, of the Vale of White Horse Iron
Works, Wantage, in the County of Berks, Engineer, 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 :-
According to my invention for the purpose of extracting gold from finely divided
gold bearing material, the material to be treated (hereinafter referred to as crushed
ore) is mechanically divided into small streams, then fed by gravity onto a wetted
amalgamated travelling surface which retains a part of the material so fed to it,
carrying the same a certain distance, then the sprinkled travelling amalgamated
surface has projected against it a strong current or currents of air free from solid
matter, and thereafter the surface so treated is passed through water. By this
method I am enabled to obviate disadvantages which I have found to result in
practice when blasting an amalgamated plate with mixed air and ore whereof a
portion is liable to rebound and carry metal down into the trough of the apparatus,
besides which a considerable amount of floating dust is given off which in some
cases would contain "float gold."
Figs. 1 and 2 of the accompanying drawings are elevations at right angles to
each other showing an apparatus according to this invention.
Fig. 3 is a diagrammatic side elevation showing a modified construction.
In the arrangement shown in Figs. 1 and 2, 1 is a rotary drum whose periphery
constitutes a travelling amalgamated surface that dips more or less at the under
side into water 2 in a suitable trough 3 and on to a watered portion of which
surface is, or are, dropped from a feed hopper 4, a fine thin stream 5, or streams,
of pulverized ore at a part 6 of the drum such that the drum being suitably large
and driven slowly, a considerable period will elapse between the delivery of the
ore to the drum and re-entry of the so sprinkled surface into the water 2 and
consequent washing off of some of the finely divided material, preparatory to
which strong blasts of air unmixed with solid particles are projected by suitable
blowers 7, 7 (or there might be only one blower and consequently one blast)
against the sprinkled surface of the drum so as to force portions of metal
thercon into intimate contact with the mercury on the drum and thus ensure
their retention.
Thus by the use as described of a blast or blasts of air particles of metal in the
material fed to the travelling surface can be gently forced into intimate contact

page_text: with the mercury on the drum practically without risk of removing mercury or
amalgan therefrom.
Although water is used to wash the surface of the drum and remove therefrom
earthy or non-metallic matter and keep the surface of the drum clean and moist, a
comparatively very small quantity will suffice, and it is not necessary to have a
running stream. As the mud collects in' the bottom of the trough 3 it can be
drawn off and allowed to settle in a tank whence the water can be used over and
over again.
The contents of the trough being heavy, in order to deliver the matter from
the trough 3, an arrangement as follows is shown:-The trough is provided with
a couple of endless chains 8 working over chain wheels 9, 9 and carrying paddles 10.
12 is an inclined shoot over which the mud is delivered by the paddles 10 when
the chains 8 are working. Other arrangements of conveying devices might be
substituted for the chains and paddles illustrated.
The drum 1 is fixed upon a shaft 13 which is carried in suitable bearing in
a frame 14 and is driven at a slow speed from a main driving shaft 15 through
a pulley 16 on that shaft, a belt 17, and a pulley 18 fixed on the shaft 13. 15ª is a
driving pulley on the shaft 15. The descent of the ore from the hopper 4 may
be controlled by a feed roll 19 driven from the shaft 15 through a pulley 20,
belt 21 and pulley 22. The spindles 7 of the blowers 7 are connected together
by pulleys 23 and belts 24 and are driven by a pulley 25 on one of them and a
belt 26 from a pulley 27 fast on a shaft 28 which is driven from the main
The chain wheels 9
driving shaft 15 by a pulley 29, belt 30 and pulley 31.
are fixed upon shafts 9 upon which are also fixed, external to the trough 3, chain
wheels 32 which are connected together by a chain 33, one of the said shafts 9
being directly driven from the shaft 13 through a pulley 34, belt 35 and
pulley 36.
I sometimes construct an apparatus with two or more troughs each with a drum
having an amalgamated surface on to which the material to be treated is fed by
gravity at oue point in the rotation of the drum whilst subsequently the surface so
sprinkled is subjected to a blast or blasts of air alone. In au arrangement of this
kind there may be two or more troughs and drums, one trough being arranged to
overflow into another either from above or below, the feed being adapted if desired
to feed two or more drums all or some only of which are subjected to an air blast
after the deposit on the respective amalgamated surface of material to be treated.
In such an arrangement floating particles of gold could be floated over from the
trough of the first drum on to the second drum and again treated and so on.
Fig. 3 indicates an arrangement adapted to treat, in a continuous manner, all
sludge settling in the trough 3, of the primary drum, over and over again. In this
case there are several troughs, each provided with an amalgamated drum 1, 1ª and
so on, the first or primary drum 1 having the material to be treated dropped on to
it, and being subjected to an air blast (or blasts) in the manner hereinbefore
described, the matter deposited in its trough 3 being delivered by a conveyor
(which may be constructed with endless chains and paddles as already described)
and the inclined shoot 12 onto the second drum 1 which is also subjected to an air
blast from a blower 7, the matter deposited into the second trough being delivered
onto a third drum, which is or may be also subjected to an air blast and the deposit
from the third trough being delivered into a settling tank whence the water is
returned to the first trough for re-use and so on.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that I do not
claim broadly the use with water of a travelling amalgamated surface onto which
material containing metal to be recovered is fed nor do I claim broadly the use of
an air blast in conjunction with an amalgamated surface but what I do claim is as
follows:-
1. The hereinabove described improved method for extracting gold from

page_text: crushed ore or material containing gold according to which a travelling
amalgamated surface is wetted, then the crushed ore or other crushed or finely
divided gold containing material is delivered in a small stream or streams upon
the wet amalgamated surface, then the crushed material so deposited on the wet
amalgamated surface has air projected against it and finally is caused to be washed
with water all in the manner and for the purpose specified.
2. For carrying into effect the improved method of extracting gold referred
to in the preceding claim apparatus constructed combined arranged and operating
substantially as described with reference to the example illustrated in Figs. 1 and 2
of the accompanying drawings.
3. Apparatus such as referred to in Claim 2 arranged in series as described with
reference to Fig. 3.
Dated this 1st day of March 1897.
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.