IMPROVEMENTS IN EXTRACTING GOLD AND OTHER METALS BY AMALGAMATION AND APPARATUS THEREFOR to be as follows
Year: 1884

page_text: I EWALD FISCHER of Wüstegiersdorf in Silesia at present temporarily residing
at Sandringham Road Dalston in the County of Middlesex Engineer do hereby
declare the nature of said invention for "IMPROVEMENTS IN EXTRACTING GOLD
AND OTHER METALS BY AMALGAMATION AND APPARATUS THEREFOR to be as
follows:
"3
The object of this invention is to completely extract from ores the gold and
other precious metals they contain and to do so at a less cost than has hitherto
been usual.
According to this invention ground or crushed ore mixed with water is brought
by mixing stirring or agitation into intimate contact with mercury for a sufficient
time to completely effect the amalgamation of the precious metals contained in
it-The ore is then discharged leaving a part of its metals in the mercury but
carrying away with it a considerable amount of mercury and part of the amalgam
in a finely divided condition-This residue or "tailings" is then subjected to the
action of an electric current from a Voltaic Battery or other generator-This
current is passed through the tailings while they are agitated and effects a complete
condensation of the metallic and gold amalgam particles, and the separation of the
rock sulphides and other constituents of the ore.
In one form of apparatus according to my invention the ground or crushed ore
is mechanically agitated with water by means of a mixing apparatus and is then
delivered into a vessel partly filled with mercury and furnished with revolving
drums wheels or rollers having surfaces designed to carry the ore downwards
through the mercury so as to bring the two into frequent and moving contact.
These drums wheels or rollers may conveniently be of various sizes and so arranged
that the ore is delivered from one to the other and the various particles are kept
in continual motion. They are driven by any suitable means such as gearing
chains or straps and are enclosed by a cover to prevent loss by splashing-A guage
may be used to indicate the height of the mercury.

page_text: From the above mentioned vessel the ore not absorbed by the mercury, and that
part of the mercury which is carried away mechanically pass into the condensing
apparatus in which there is a vertical shaft having connected with it two or more
amalgamated copper plates placed obliquely. These plates by means of sliding
contacts on the spindle receive during each revolution a positive and negative
current alternately from an electric generator and thus a practically continuous
current in one direction is maintained in the tailings the result being that the
metallic particles are immediately condensed by the copper plates and then run
into the mercurial amalgam accumulated below.

page_text: We EWALD FISCHER, of Wüstergiersdorf in Silesia late temporarily residing at
Sandringham Road, Dalston, in the County of Middlesex, at present residing at
14 Montague Road, Dalston, aforesaid Engineer and MAX WILLIAM WEBER, of
25 Leadenhall Buildings, Leadenhall Street, in the City of London, Merchant
do hereby declare the nature of said invention for "IMPROVEMENTS IN EXTRACTING
GOLD AND OTHER METALS BY AMALGAMATION AND APPARATUS THEREFOR" and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
The object of this invention is to completely extract from ores the gold and
other precious metals they contain and to do so at a less cost than has hitherto been
usual.
According to this invention, ground or crushed ore mixed with water is brought
by mixing, stirring, or agitation into intimate contact with mercury for a sufficient
time to completely effect the amalgamation of the precious metals contained in it.
The ore is then discharged leaving a part of its metals in the mercury but carrying
away with it a considerable amount of mercury and part of the amalgam in a finely
divided condition. This residue or "tailings" is then subjected to the action of an
electric current from a voltaic battery or other generator. This current is passed
through the tailings while they are agitated and effects a complete condensation of
the metallic and gold amalgain particles and the separation of the rock sulphides
and other constituents of the ore.
In one form of apparatus according to the invention the ground or crushed ore
is mechanically agitated with water by means of a mixing apparatus and is then
delivered into a vessel partly filled with mercury and furnished with revolving
drums wheels or rollers having surfaces designed to carry the ore downwards
through the mercury so as to bring the two into frequent and moving contact.
These drums wheels or rollers which may be of various sizes are so arranged that
the ore is delivered from one to the other and the various particles are kept in
continual motion. They are driven by any suitable means such as gearing chains
or straps and are enclosed by a cover to prevent loss by splashing. A gauge may
be used to indicate the height of the mercury.
From the above mentioned vessel the ore not absorbed by the mercury, and that
part of the mercury which is carried away mechanically pass into the condensing
apparatus in which there is a vertical shaft having connected with it two or more
amalgamated copper plates placed obliquely. These plates by means of sliding
contacts on the spindle receive during each revolution a positive and negative
current alternately from an electric generator, the result being that the metallic
particles are immediately condensed by the copper plates and then run into the
mercurial amalgam accumulated below.
Referring to the accompanying 4 sheets of illustrative drawings, Fig 1 is a
vertical section of apparatus according to the invention and Fig 2' is a plan or top

page_text: view of the same. Fig 3 is a transverse section and Fig 4 an end view of the
said apparatus. Figs 5, 6 and 7 are detail views drawn to an enlarged scale and
hereinafter referred to. The same letters of reference are used to denote like parts
in each of the figures where they occur.
a is the mixing chamber into which ground or crushed ore mixed with water, is
continuously run and wherein the same is mechanically agitated by a stirrer
constructed with blades 6¹ secured to a frame b' carried by a vertical spindle b³ the
lower end b of which is pivotted in the bottom of the chamber a. The upper end
of the said spindle 63 has a bearing in the cross piece or frame 65 and is provided
with a mitre wheel b whereby it receives motion from the main driving shaft c of
the machine through the intervention of the pulley c¹ strap or band c³, pulley c³
shaft c¹ and mitre wheel c as will be readily understood. Tho pulley and mitre
wheel care fixed to the shaft c carried in bearings c supported by the pillars or
frame secured to the base d of the machine. a' a' are similar pillars for
supporting the chamber a above the base plate & The ore and water are thoroughly
agitated in the vessel or chamber a whence a continuous stream runs off through
the opening a into one end of the vessel or chamber e which is partially filled with
mercury. This end of the vessel or chamber e is provided with a cover ns
indicated in dotted lines at c¹ furnished with a slot or opening through which the
mixed water and ore pass, an inclined plate or diaphragın e also indicated in doited
lines, being preferably employed to conduct the said water and ore direct to the drums,
wheels, or rollers hereinafter described. The rate of flow of the mixed water and
ore through the opening a² is controlled to any desired extent by a valve a³ carried
by a lever a pivotted at a to a projection aº extending-from-the-under surface of
the vessel or chamber.a.-f-fare revolving drums, wheels, or rollers mounted on
the shafts c and g so as to revolve in the vessel or chamber e, and provided with
grooved or serrated surfaces as shown designed to carry the ore downward into and
to well agitate it with, the mercury contained in the said vessel, or chamber. The
shaft g to which the drum wheel or roller f¹ is secured receives its notion from
the main driving shaft c carrying the drum wheel or roller f, by means of the gear
wheels g* c* mounted on the said shafts g and c respectively. i is a cover over the
druins, wheels or rollers f, f¹ to prevent loss of materials by splashing, also
unauthorized abstraction. The vessel or chamber e is also provided with another
cover e extending conveniently over the top of the vessel or chamber hereinafter
referred to. The covers ei and e¹ are capable of being locked to the said vessel or
chamber e to prevent improper abstraction of amalgam therefrom. e' is a recess or
channel in the bottom of the vessel or chamber e in which the amalgam of mercury
with gold silver or other metal collects when formed, the bottom portion of the said
vessel or chamber e, on each side of the recess or channel e being inclined thereto
to assist in the collection of the amalgam therein..
The ore or precious metals not absorbed by the mercury and such part of the
mercury and amalgam as may be suspended mechanically in a fine state of sub-
division in the water pass together through an opening at j into the condensing
vessel or chamber k, provided with a vertical shaft carrying the obliquely arranged
amalgamated copper plates m shown to an enlarged scale in Figs 5 and 6. These
plates are preferably arranged to be partly immersed in the mercury m at the
base of the vessel or chamber . The shaft is carried in bearings 1, 1, and is
provided at its upper end with a mitre wheel gearing with and receiving motion
from another mitre wheel n fixed to the shaft n¹ carried in bearings n2 n² and
actuated from the shaft g by means of the pulley g¹; belt or band g² and pulley n³
as will be readily understood.
A commutator or collector is fixed upon, but insulated from the shaft l. It
comprises the main portions or rings 0, 0, 0³ shown separated from each other in
Fig. 7.
These three main portions or rings 4, 02, 0³ are each composed of two unequal
metal segments or portions separated from each other by a short length of insulating

page_text: material, the length of the longer segment or portion in each case being preferably
about five sixths (3/ths) that of the circumference of one of the main portions or
rings oo or os, whilst the length of the shorter segment in each case is
about (th) that of tho said circumference for a purpose hereinafter specified.
The said segments are each secured to and carried by a disc of insulating material
attached to the vertical shaft l. 0, 0; 06, 07; and o³, o represent the unequal
segments of the three main portions or rings o¹, 02, 03 respectively, whilst olo
represents insulating material in each case.
The metal segment o' is electrically connected to the segment oⓇ by the connec-
tion p, whilst the segment o, is electrically connected to the segment 0° by the
connection p. The segments o³ and os are electrically connected with the oblique
amalgamated blades or plates m and with a flat rotary plate m¹ immersed in the
mercury m*, by metallic wires or connections p* p* passing downward through a
vertical hole formed in the shaft or spindle as shown clearly in Fig 5. q', 9, 9³
are metallic contact strips or brushes carried by but insulated from a projection q*
from a cross piece q' supported by the frame of the machine. The said contact
strips or brushes q, q, q³ bear against the peripheries of the three portions or
rings ooo respectively and are in connection with the binding screws or
terminals,, (see Fig 7) The binding screws or terminals and are
electrically connected to the positive and negative poles respectively, of a dynamo
electric machine or other source of electrical energy, whilst the binding screw or
terminal is electrically connected by the connection p³ with one or more fixed
amalgamated copper or other metallic plates s immersed in the water in the vessel
or chamber k. The action of an electric current in condensing or depositing finely
divided precious metals, mercury, and amalgam from the water and other substances
with which they are mixed is as follows. Supposing the terminals r¹ and ³ to be
in electrical connexion with the positive and negative poles respectively of an
active-dynamo electric machine or other source of electrical energy then the electric
current will pass from the terminal to the contact strip or brush q' segment o*
connection p, segment of contact strip or brush q' terminal 2 connection p³ to the
plate s. The electric current then passes across through the water in the vessel or
chamber to the mercury m* and amalgamated copper plates m, and m³, wires or
connections *, segment o contact strip or brush q3 and negative terminal 3 thus
completing the electric circuit. During the time the current is passing in the direction
and manner above described, the plate s constitutes the positive pole, electrode, or
anode, whilst the inercury m* and copper plates m and m¹ constitute the negative
pole, electrode or cathode to which the finely divided precious metals, mercury and
amalgam are attracted from the water as will be readily understood, and thus
recovered. The above actions will continue for about five sixths of a revolution of the
shaft or whilst the larger segments o³, 0º, and 08 are revolving in contact with their
strips or brushes q₁ q² q³ respectively. As the shaft and portions or rings o¹, 02, 0³
revolve the strips or brushes come into contact with the short strips of insulating
material o for a short interval during which time the current is temporarily or
momentarily stopped. As the revolution continues the brushes come into contact
with the smaller segments o³ 0 0° whereupon the direction of the current through
the apparatus and the polarity of the poles or electrodes is reversed, the current now
passing from the positive terminal to the contact strip, or brush q', segment o
wires or connections p*, p*, to the plates m, m' and ruercury m* which now
constitutes the positive pole electrode or anode for about one sixth of a revolution
of the shaft . The current passes across through the water to the plate & which
now constitutes the negative electrode or cathode to which the finely divided
precious metals, mercury and amalgam present in the water are attracted for the
said one sixth of a revolution, the electric circuit being completed through the
connection p³ terminal, contact strip or brush q², segment o, connection p',
segment o contact strip or brush q³ to the negative terminal, as will be clearly
understood on reference to Fig 7. The actions above described take place during

page_text: each revolution of the shaft l. The mounting of the blades m on a rotary shaft
ensures that the water containing the finely devided metals shall be well agitated
and the whole of the metals be brought within the influence of the electric current,
whilst the reversal of the current during a portion of each revolution ensures that
the surface of the mercury m* and amalgamated plates m m' and 8 shall remain
clean and consequently active for the purpose of retaining the subdivided metals
brought into contact therewith as above described.
As the mercury m* forms a reservoir for the precious metals and amalgam it is
preferred to make it the negative pole electrode, or cathode for the greater portion
of each revolution. t is an outlet pipe for water to flow from the vessel or chamber .
The height of the upper end of this pipe may be regulated by the screwed
rod connected thereto at t and operated by the nut or hand wheel t³ in a manner
that will be readily understood; thus the level of the water in the vessel or
chamber may be maintained at any desired height. By these means also the
water, water and sand, and other heavy particles of the ores treated which have
collected in the said vessel or chamber during the operation of the machine, may
be drawn off consecutively by lowering the top of the pipe t to the required extent,
at any desired intervals to clean or clear the apparatus and ensure its efficient
working. The screw arrangement for lowering the said pipe t is such however
that the top of the pipe t cannot be lowered sufficiently to draw off the mercury
or amalgam from the apparatus. In lieu of the arrangement just described, a
series of holes may be formed in the side of the vessel or chamber k communicating
with its interior.
The said openings may be arranged one above another, the lowest_one_being
above the surface of the mercury_or_amalgam,-and-controlled by a slide valve
provided-with-an outflow pipe or opening. The valve may be operated by a lever
or screw or other convenient means so that its outflow opening may be brought
opposite to either of the openings above mentioned for the purposes stated or the
said openings may be entirely closed if desired. Instead of a series of openings
one slot or opening may be employed provided with a slide valve operated as
above, the object in each case being to allow the water to run off at any. desired
level, or to draw off the water, sand or other particles consecutively thus cleaning
or clearing the apparatus as above stated, without risk of drawing off any of the
mercury or amalgam. u is a cock or valve, normally kept closed, for drawing off
the mercury and amalgam from the bottom of the chamber when desired or when
sufficiently enriched by precious metals. The said bottom and the bottom of the
recess e are made to incline to the part k¹ of the vessel or chamber to which the
cock or valve u is attached, in order that the whole of the mercury and amalgam in
the apparatus may be drawn off.
When the ores to be treated contain sulphides we prefer to add caustic soda to
the water to be mixed therewith as is at present sometimes practised, whilst in all
cases when treating refractory ores, sodium, or sodium amalgam should be added to
the mercury employed with a view to ensure a satisfactory result.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is
1. The improved method or process herein-above described of extracting precious
metals such as gold and silver from substances containing the same.
2. In apparatus for extracting or collecting by amalgamation precious metals
such as gold and silver from substances containing them the use of electric poles or
electrodes caused to become alternatively positive and negative substantially as
herein before described.
3. The use for extracting precious metals such as gold and silver from substances
containing the same of mixing apparatus amalgamating apparatus and rotary blades
or plates caused to become alternately positive and negative poles or electrodes
substantially as herein before described.

page_text: 4. The combination of parts constituting the improved apparatus constructed,
arranged, and operating as shewn in and described with reference to the drawings,
for extracting precious metals such as gold and silver from substances containing
the same as above set forth.
W. LLOYD WISE,
Agent for the Applicants.