Improvements in Amalgamating the Precious Metals and their Ores and the like, and in Apparatus therefor.
Year: 1892

page_text: Date of Application, 7th Mar., 1892
Complete Specification Left, 7th Dec., 1892-Accepted, 21st Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Amalgamating the Precious Metals and their Ores
and the like, and in Apparatus therefor.
We, THOMAS EVANS, of Fronfelin, Barmouth, North Wales, Mining Engineer,.
and HENRY CHRISTOPHER BUNKELL, of 15 Alexandra Villas, Finsbury Park, in
the County of London, Surveyor, do hereby declare the nature of this invention to
be as follows:-
Our invention relates principally to the construction of an improved amalgamator
by means of which ores, alluvial deposits, soil, or earth which contain the precious
metals, and tailings from mines and the like, may be treated, and the contained
metal amalgamated and extracted therefrom.
According to our invention a hollow vertical shaft is mounted on a suitable bed
so as to revolve on a pivot at the base thereof, such hollow shaft is fitted at top,
with a hopper into which the pulverized ore or other material to be treated, which
is hereinafter referred to as pulp," is introduced, preferably direct from the
crushing or pulverizing apparatus, and near the base of the hollow shaft is a series
of openings through which the pulp may pass into the amalgamating tank, the
centre of which is occupied by the said shaft. To the said hollow shaft a series of
horizontal arms, preferably curved, are fixed so as to be carried round when the
shaft is made to revolve, and a series of vanes and stirrers attached thereto, or to
the shaft, operate the pulp as hereinafter described.
The base of the tank is constructed with a series of channels, or hollows, which
when the apparatus is in use, are filled with mercury and which may conveniently
be arranged in a series of concentric circles with other channels arranged radially
connecting them and a channel, or passage, leading therefrom to a draw-off tap
or cock.
Means are provided for communicating a rotary motion to the shaft and arms &c..
from any accessible source of power.
When pulp is introduced into the hopper it passes down the hollow shaft and
through the lateral openings in it and is swept by the stirrers and vanes over the
floor or base of the tank and thus over and in contact with the mercury in the
channels which is thus brought intimately into contact with every part of the pulp
which by the revolution of the apparatus is gradually swept outwards towards the
circumference of the tank, where it is ultimately discharged.
The gold or other precious metal contained in the pulp is thus amalgamated and
taken up by the mercury in the channels, and this, when sufficiently charged with
the precious metal, is withdrawn by means of the draw-off' tap and treated in the
usual well known manner.
Dated the 7th day of March 1892.
NEWNHAM BROWNE,
Agent for the Applicants.

page_text: T
Improvements in Amalgamating the Precious Metals and their Ores
and the like, and in Apparatus therefor:
We, THOMAS EVANS, of Eronfelin Barmouth, North Wales, Mining Engineer,
and HENRY CHRISTOPHER BUNKELL, of 15 Alexandra Villas, Finsbury Park, in
the County of London, Surveyor, 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 principally to the construction of an improved amalgamator
by means of which ores alluvial deposits, soil, or earth which contains the precious
metals, and tailings from mines and the like, may be treated and the contained
metal amalgamated and extracted therefrom.
According to our invention which we have illustrated in the accompanying sheets
of drawings wherein
Fig. 1. is a vertical section of our apparatus on a somewhat larger scale than the
subsequent figures,
Fig. 2 a plan of the same with the hopper and gearing removed to shew fully
the parts below,
Fig. 3. is a plan of the tank and Fig. 4 an elevation of part of the tank showing
one outlet and perforated screen,
A hollow vertical shaft A is mounted in the centre of a circular tank B on a
pivot a working in a socket 6 in a slab which may be built into the floor of the tank
if the tank is of cement or masonry as represented in the drawings or if the tank
be, of other materials for instance iron the socket may be sunk in such material or
bushed therein. At the top of the hollow shaft is fixed a, hopper C through which
the material to be treated previously prepared by grinding pulverizing washing or
the like or one or some of them is introduced into the hollow shaft; such prepared
material, which is in a wet state is bereinafter called "pulp" and preferably is
delivered into the hopper direct from the crushing or pulverizing apparatus. The
lower part of the hopper c forms a tubular bearing on which the shaft A works.
The hollow shaft A is pierced by openings d d through which the pulp passes into
the tank. To the exterior of the hollow shaft are attached a series of preferably
three or four blades E and a series of horizontal arms E which are preferably
curved as shewn in Fig. 2. To these arms are attached stirrers preferably with
three prongs to each and the first and each subsequent stirrer on each arm being
placed at a distance from the centre of rotation differing from that of the corre
sponding stirrer on each of the other arms and each stirrer being preferably, attached
to the arm with a screw nut or nuts, or other means of adjusting it accurately to
the depth between the bar and the bottom of the tank. The ends of the arms may
be made to enter an annular recess G in the wall of the tank and are provided with
a small wheel or roller g to lessen the friction.
The shaft is fitted with any convenient means for imparting: rotation, such for
instance as the bevel wheel H gearing with the corresponding wheel on the
shaft.
The internal surface of the bottom of the tank B is traversed by cocentric
annular channels J and radiating channels j both of which are intended to contain
the mercury. K are channels through the bottom of the tank through which the
mercury is drawn off when sufficiently charged with the metal. k are cocks closing
such channels and regulating the flow of the mercury.
The tank has several, preferably four, openings L closed with perforated screens 1,
each of the perforations being provided with a cock or other means of closing them,
through which the exhausted pulp passes as it reaches the circumference of the

page_text: tank. The tank is supported on piers M or the like so as to afford access to the
cocks beneath it.
In operating with our apparatus the channels J and jare filled, or nearly so,
with mercury, some water is introduced into the tank and then pulp is passed in
through the hopper C. The tubular shaft A and attached apparatus being made
to rotate the pulp passes through the openings d, and is caught by the blades E,
which push it outwards to the stirrers, by which it is agitated and caused to pass
over the mercury in the channels, and passed outwards centrifugally towards to
circumference, where it escapes thoroughly exhausted through the openings L and
cocks in the perforated screens l.
The mercury when sufficiently charged with the precious metal is drawn off
through the cocks & and treated in the usual manner.
It will be at once perceived that a comparatively small quantity of mercury
suffices for the treatment of a large quantity of pulp every part of the pulp being
by this apparatus brought so thoroughly into contact with the mercury as it is
swept again and again across the channels and is gradually carried outwards from
the centre and thus this apparatus is specially adapted for the treatment of the
pulp containing only a small percentage of the precious metal.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed we declare that what we
claim is:
1. The herein before described apparatus for amalgamating and extracting the
precious metals from their powdered ores matrices and the like substantially as
described and shewn in the drawings.
2. An amalgamating apparatus for extracting the precious metals from their
ores alluvial deposits soil earth tailings from mines and the like containing such
metals comprising a tank having mercury holding channels in its floor or bottom
outlets for the exhausted pulp and for the mercury a central tubular shaft through
which the ore is introduced and rotating stirring apparatus substantially as herein-
before described.
3. The combination in an apparatus for amalgamating the precious metals of a
hollow shaft such as A, blades and arms such as E and F, stirrers such as f, with a
tank or receptacle B, having channels such as J and j and outlets such as K and L
for the purpose and substantially as described.
4. The use of apparatus for extracting the precious metals by amalgamation
constructed and operating substantially as herein before described.
Dated this Sixth day of December 1892.
THOMAS EVANS.
HENRY CRIS. BUNKELL.