Improvements in and relating to Methods of Washing, Concentrating, and Amalgamating Ores, and in Apparatus therefor.
Year: 1894

page_text: Date of Application, 13th Nov., 1894-Accepted, 13th Apr., 1895
COME LEID SPECIFICATION.
Improvements in and relating to Methods of Washing, Concentrating,
and Amalgamating Ores, and in Apparatus therefor.
I, CHARLES FREDERICK PIKE, a citizen of the United States of America,
residing at 2038 Nicholas Street, in the City and County of Philadelphia and
State of Pennsylvania, one of the United States of America, Mechanical
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 :-
My invention has relation to the art of separating precious metals from their
ores or gangue, and it has for its object the provision of means whereby the
separation is more thoroughly and more economically effected than is possible
under processes hitherto employed, or with apparatuses as heretofore constructed.
My invention is more particularly designed for working placer gravel, in the
profitable working of which it is necessary to pass large quantities of the dirt or
gravel through the machine rapidly, and it is essential that all of the gravel or
dirt should be thoroughly washed.
As such large quantities of the gravel are passed through the machine, the
black-sand contained therein accumulates very rapidly and fills and packs in the
riffles, which then become inoperative, the metal passing over the filled riffles with
the black-sand, unless the riffles are very frequently cleared, which is impracticable.
This occurs in all placer working machines or apparatus wherein riffles are employed,
whether such machines be sluice boxes or specially designed machines.
The loss of metal due to the packing of the black-sand in the riffle diminishes
the output of the metal or the efficiency of the machine, as the recovery of metal
is not as large as would be the case if such packing did not take place.
This part of my invention has for its object to avoid such disadvantages, and
to this end I keep the black-sand alive, or in a state of intermittent suspension
during its passage over the riffles by imparting to them a reciprocating movement
below the surface of a body of water, which also results a more thorough washing
and separation.
The screens and riffle plates are so constructed that their forward movement
positively advances the material through the water, and that as they make their
return movement, said material is left in a state of temporary suspension above
such screeus or plates. This successive suspension in water of the material more
readily admits of the metal particles falling through the gravel, while the black-
sand is prevented from accumulating and packing in the riffles, in view of the fact
that at each forward movement of the riffle plate the sand is thrown upward and
forward and held temporarily in suspension in the water. This admits of metal
readily falling through the sand back of the riffles, where it is retained, while the
saud is continually caused to advance, having therefore no opportunity to pack in
the riffles, so that they cannot become inoperative. Such being the case, metal
particles do not pass off with the black-sand, hence, a material increase in the
amount of precious metal recovered.
To more effectually accomplish these results I employ a series of screens
which are preferably inclined downward from their feed to their discharge end, and
are reciprocated through a body of substantially quiescent water.
The first part of my invention consists, therefore, essentially in the method of
and in apparatus for the more effectual or thorough and economical separation of
precious metal from placer gravel.

page_text: The apparatus may, however, be variously modified according to the require-
ments of service; thus, for instance, it may be made portable, by mounting the
same on a truck, for working on land, or on a scow or other vessel, for working
river bottoms. On the other hand, a plurality of washers, concentrators or
amalgamators may be arranged in series and made portable for land or water service
for the purpose of more thoroughly separating the metal from the gravel ore or
gangue, and for the purpose of separating the impure from the free, pure metal, so
as to avoid the passing of the impure metal to the amalgamator, and for the purpose
of utilizing over and over again the water flowing through the system when the
apparatus is employed in localities where water is scarce.
The second part of my invention consists, therefore, essentially in the arrange-
ment of a plurality of washers or separators and concentrators in series, whether
portable or stationary, and in the means for working river bottoms.
The third part of my invention has relation to amalgamators, more particularly,
and it consists essentially in the provision of means whereby the ore is fed to the
amalgamator and deposited upon the amalgamator plate, and whereby the waste
material is discharged therefrom and from the amalgamator in such manner as to
more effectually avoid the rubbing off of the amalgam from the plate by the waste
material, or in other words, to prevent the waste material from sliding upon or
over the amalgam plate, to deteriorate the latter. This I accomplish by depositing
the ore vertically on the plate, whereby it is carried to the discharge of the
apparatus, at which point the waste material is lifted vertically from the plate
and discharged by suction.
Apparatus of this character may also be variously modified. For instance, n
moving or rotating body of mercury may be employed, with stationary feeding and
suction-discharge devices; or a stationary body of mercury with moving or
rotating feeding and suction-discharge devices may be employed; or the material-
ore or gangue or placer gravel-impelled by a jet of water, for instance, may be
caused to move over a body of mercury from the feed to the suction-discharge.
In such apparatus the suction-discharge is adjustable relatively to the body of
mercury, and in order to avoid the lifting and consequent loss of amalgam with
the waste material, I provide means whereby this is avoided, even when the inlet
to the suction-discharge is adjusted close to the body of mercury. Furthermore,
the separation of precious metal from its ore or gangue, and more particularly
from the black sand in placer gravel may be effected with or without the use of
amalgam plates, the separation being here effected by causing the material mixed
with the water to flow in proximity to one or more magnets, means being provided
for alternately making and breaking the circuit through said magnet or magnets,
whereby the black sand is alternately attracted and allowed to fall again, being
thus held in suspension for a time, whereby the particles of metal are left free to
drop upon a stationary or movable surface, to be collected after leaving the same,
and this constitutes the fourth part of my invention.
Apparatus of the kind above referred to may also be variously modified in their
construction, while the inclined receiving table may be stationary, or may receive
to-and-fro or jigging motion. On the other hand, when the separation is effected
by amalgamation with a body of mercury or amalgam plate, it is desirable, in fact,
necessary, to keep the surface of the mercury bright and clean, and this is
effectually attained by means of magnets, which may be so arranged in proximity
to the suction-discharge device as to be either separately discharged from the
apparatus, or caused to be deposited within the influence of said suction-discharge
for removal with the light or other waste matter of the ore. In the first case the
black sand particles are discharged from the apparatus as a clean or approximately
clean by-product, and in the other they form part of the common discharged waste
matters. This mode of operating has the further advantage in that the force of
suction does not need to be of a maximum degree, which would be required if such
force were employed to first lift the sand particles from the mercury or amalgam
plate and then effect their discharge. On the contrary, the degree of such force

page_text: may be reduced to a minimum, or so as to discharge such particles along with the
lighter waste matter, hence all tendency of such force to lift and discharge the
mercury is avoided, while the surface of the mercury is kept clean and bright, and
retains its full efficiency. Such apparatus is preferably provided with a secondary
discharge device interposed between the feed and suction-discharge devices for
recovering the very light waste material instead of removing the same with the
heavier waste matter through the main discharge. This results in a reluction of
the work to be done by the main discharge, and also admits of the lighter waste
and any contained float metal to be conveyed directly to the amalgamating devices,
thereby expediting the operation of the apparatus. On the other hand, instead of
stationary magnets, movable magnets may be employed, and a brush or wiper
combined therewith.
The fifth part of my invention consists in the provision of means whereby the
ore gangue, after leaving the separator or amalgamator, is divided into a series of
separate streams and conducted over auxiliary amalgamator plates, whereby a more
rapid and thorough separation is effected, and such means may be combined with a
separator or concentrator of the kind hereinabove referred to, or with an
amalgamator of special construction.
I will now describe the several parts of my invention in detail, reference being
bad to the accompanying drawings, in which-
Figure 1 is a plan view, and Figures 2 and sections taken respectively on
lines x and y y of Figure 1, of apparatus illustrating the first part of my inven-
tion. Figures 4 and 5 are plan and end views, respectively, of the preferred
construction of a rocking screen, and Figure 6 is a detail plan of a modified form
of one of the concentrating chambers of the apparatus. Figure 7 is an elevation
of an apparatus for working river bottoms, and Figures 8 to 13 are detail views
thereof. Figures 14 and 15 are elevations of apparatus similar to Figure 7,
illustrating the arrangement of washers, concentrators or amalgamators in series,
and Figure 16 is a detached detail elevation of a modified arrangement of the
washers, concentrators or amalgamators and the conveyors. Figures 7 to 16
illustrate the second part of my invention.
Figure 17 is a vertical sectional view of an amalgamator such as shown in
Figures 14 and 15, the suction-discharge being provided with a mercury arresting
plate; Figure 18 is a like view illustrating a mercury containing vessel combine.l
with a revoluble feed pipe and suction-discharge pipe. Figures 19 and 21 are also
vertical sectional views of amalgamators illustrating further structural modifica-
tions, Figure 22 being a plan view of Figure 21, while Figure 20 is a fragmentary
sectional view showing a modification of the construction illustrated in Figure 19;
Figure 23 is a detail view of Figure 22; Figure 24 is a vertical sectional
view of the preferred construction of amalgamator involving the principles
illustrated in Figures 19 and 21, Figure 25 being a plan view thereof, and Figure 26
a vertical section seen from a different point; Figure 27 is an elevation, partly
broken away, of partition plate in the ore receiving vessel, and means thereon for
regulating the height of such partition; Figure 28 is a plan broken away showing
jet tubes at the exit end of the feeding flume or trough for the washer or con-
centrator; Figures 29 and 30 are, respectively, an elevation and sectional elevation
of different forms of jet supply tubes for the ore washer or concentrator for
location adjacent to the suction discharge; Figure 31 is a partial plan of mercury
containing vessel, and a horizontal section of the partition of the receiving vessel,
and Figure 32 is a sectional elevation, partly broken away, showing the suction
passage located within the washer or concentrator below the water level thereof;
Figure 33 is a fragmentary vertical section of an amalgamator or washer, containing
a body of mercury, a feed device, and a suction-discharge device distant from each
other, and a jet nozzle or nozzles for forcibly spreading or dispersing the ore or
gangue after it is fed to the washer. Figures 34 and 35 are sectional views of two
types of washers, concentrators or amalgamators illustrating means for preventing

page_text: the mercury being drawn out through the suction-discharge pipe; Figure 35ª being
a detail thereof.
The above-described Figures, 17 to 354, are illustrative of the third part of my
invention.
Figure 36 is a vertical sectional view of an ore washer or concentrator, illustrating
the arrangement of a magnetic field between the feed pipe and the suction-discharge,
and an auxiliary magnetic field at or near the inlet to said suction-discharge, and
means for propelling the ore or gangue from said feed pipe to said suction-discharge;
Figure 37 is a fragmentary sectional view illustrating the auxiliary magnet in its
relation to a revolving mercury containing vessel. Figure 38 is a vertical sectional
view of an ore washer or concentrator in which receiving pockets are provided at
the feed and discharge ends; Figure 39 is a like view, the apparatus being provided
with a jigging riffle bottom or plate, and Figure 40 illustrates a belt conveyor for
the ore that may be substituted either for the fixed bottom, Figure 38, or the
jigging bottom, Figure 39; Figure 41 is a sectional view of an amalgamator
illustrating revoluble magnets (combined with a brush or wiper) interposed between
the feed device and suction-discharge; Figure 42 is a like view illustrating a
modified arrangement of traveling magnets; Figure 43 is a plan view illustrating
a preferred and more complete construction of apparatus involving the principles
illustrated in Figures 41 and 42, and Figure 44 is a distorted vertical sectional
view of Figure 43.
Figures 36 to 44 inclusive are illustrative of the fourth part of my invention, the
fifth part thereof being illustrated in the following figures of drawings, to wit:-
. Figures 45 and 47 are elevations, partly in section, of ore washers and con-
centrators or amalgamators, in which suction is resorted to to propel the material
through the apparatus, illustrating means whereby the ore is divided into different
streams by means of gangs of plates or chutes; Figure 46 is an end elevation of
the same, partly in section, detached from the frame; Figure 47 is a view similar
to Figure 45, illustrating means for separately adjusting the inclination of the
gangs of amalgamated plates, and Figure 48 is a vertical sectional view of the
arrangement shown in Figures 45 to 47, illustrating a simplified construction,
the adjusting devices being dispensed with.
Referring now to Figures 1 to 6 inclusive, which illustrate the first part of my
invention.
The washer or concentrator shown in Figures 1, 2 and 3 is of suitable construc-
tion and relates to that type in which the ore is screened in or below the surface of
a body of water, and the black-sand is passed over a riffle plate below the screens,
which may be of any form; a indicates the vessel a¹ a¹, the supports for the screens
pivoted at a³, said supports provided on their proximate faces with bearings a³ for
journals at on the screens a³, a, a, Figure 3, which screens may be open at one
or both ends. Below the lower screen a is arranged a riffle plate a³, Figures 2
and 6, provided with an outlet chute a at right angles to the screen, or it may be
constructed as shown in Figure 6. The chute a leads to the receiving chamber at
for the materials from the riffle plate ud, in which chamber is located the suction-
discharge device. The screens a, a, a', are inclined downwardly in the direction
of their discharge end a¹³, the inclination being preferably such that the ore
therein will not have a descending motion due to gravity when the screens are at
rest. The ore is advanced by the screens in their forward movement, said screens
withdrawing from the ore in their backward movement, leaving it suspended, to
admit of the metal particles falling freely; the suspended ore in descending is
again met, shaken and advanced by the next advance movement of the screens,
and so on, until the waste matter or remainder of such ore on the screens is
discharged at a¹³. The suspended ore or waste matter on the screens is therefore
subjected to successive violent bumpings or shakings. Owing to the suspension of
the gravel in the water and the rapidity of the reciprocations of the screens,
which may be of a high speed, or as the requirement of service demands, and

page_text: furthermore, the violent agitation to which the ore is subjected, as well as that
due to the friction of the water, effects a thorough washing of the ore for securing
a maximum separation of the metal in a minimum period.
This mode of washing is to be distinguished from that effected by revolving
screens, wherein the ore is merely tumbled or rolled over as it advances along the
screens, and is not subjected to any violent shaking, as in applicant's case, and
wherein the operation is a slow one, and not of maximum effectiveness. It is also-
distinguished from washing and screening ores in shaking screens not immersed in
water, but in which the water and ore are either fed together or separately on the
screens, in which case the washing is only effected by the fall of the water, and the
separation by the movement of the screens. The receiving chamber a10 has a
screen bottom a", below which is a collecting pocket or chamber a", wherein the
metal particles accumulate, said pocket having a removable cover a".
The discharge device is represented as a suction pump a*, the suction pipe a¹ of
which is vertically adjustable to and from screen a", and to this end I preferably
construct it of rubber with a metal inlet a" of oblong shape corresponding to the
width of the screen a¹, from which the waste matter is discharged, while the
metal particles drop into a pocket a¹. The tube a¹ is made of telescopic sections
secured together by set screws a¹8. If desired, one of said sections, especially the
metal or upper section, may be provided with an opening covered by an adjustable.
slide a for regulating the suction-discharge. The lateral adjustment of suction
pipe a is affected by a screw rod a20 for the purpose of altering the position of
the inlet of said pipe a" to and from screen a". The screens a, a, a discharge
into a pocket a", and the waste material is taken out of vessel a by an elevator a*
and discharged into a chute a³, preferably provided with a removable cover a
Figure 2, to prevent access thereto by unauthorized persons. This chute a³, is of
considerable length, and provided with cross riffles a" for catching any pieces of
metal too large to pass through the screens a³, a, a'. The chute a terminates in
a screen plate a26, from which the waste matter escapes while the water passing.
through said screen is returned to the vessel a by a conductor a".
The discharge
from the suction pump leads to a screen a28, from which escapes any waste matter
not fine enough to pass through said screen, while the water and finer material-
falling through the screen may be conducted to an amalgamator or another con-
centrator, not shown. If desired, a branch pipe a, Figure 2, from the outlet pipe
of the suction pump may be conducted to the discharge end of the elevator a", to
thoroughly wash the bulky waste of any metal particles adhering thereto or
segregated therewith.
A separate water supply pipe may be used for the flume a, Figures 1 and 2,
feeding the ore to the screens, or said pipe may be a branch from the suction pump,
as shown in dotted lines in Figure 3. Chute a Figure 3, is located a distance
above screen a¹, so that matter discharged therefrom will have a drop or fall
to said screen, thereby dispersing or spreading the particles of the same, to permit.
the metal particles to easily separate from the waste matter before the latter is.
taken up by the suction-discharge. Furthermore, such drop is provided for the
introduction of a vertical screen, a³, between screen a¹, and chute a, for water
to circulate through to aid such dispersion, and if desired, screen a¹ may be pivoted
to screen a³, and provided with an adjusting screw (shown in dotted lines Figure 3).
for adjusting its inclination.
The mesh of the screens is such as to suit the requirements of service; in
Figures 2 and 3 the screen a³ has the finest mesh, and the upper screen a' the
coarsest. A cheap and durable form of screen is shown in Figures 4 and 5, the
parts of which may be cheaply renewed when worn. They may be constructed of
angle iron sides a³, connected by end and middle cross pieces a³³, to which the screen
bottom is fastened.
The frame as is rocked by any suitable means, as by a revoluble crank disc and
a link connection, Figures 1 and 2. Since all the screens a³, a, a' are supported
by the uprights a³, they will be reciprocated together, but as they are located in

page_text: different planes the amplitude of their reciprocating motion varies, the coursest
having the greatest extent of motion to have a maximum shaking, while the finest
has a minimum shaking.
In Figure 6 the riffle plate as is shown so as to extend to near the discharge end
of screen a³, and is provided with transverse riffles a³ for catching the particles of
metal as they travel along its surface; its outer end 35 is cut away at an angle, and
is provided with small strips a³ for distributing or spreading the discharge upon the
chute a fastened to the said riffle plate and rocking therewith.
The operation is as follows: The ore is fed to the top screeen a', and all material
too large to pass through the mesh thereof is discharged therefrom, while the
material that passes through the meshes of said screen drops onto screen aⓇ, is there
likewise acted upon, the operation being repeated on screen a³, so that all waste
matter from the sub-screens is discharged onto a common elevator a2, conveyed to
fiume a, and washed before passing from chute 28, so that any metal escaping
with such waste is recovered in the flume riffles, while the water flows back to
vessel a. The concentrates from screen a³ fall upon riffle plate as, and are there
subjected to the same shaking movements as the ore, but less violently, and are
thereby advanced at each forward movement of said riffle plate and held in
suspension in the water during the return movement of said plate, so as to keep
them alive or scattered during their passage over the plate. The packing of the
black-sand in the riffles of the plate is thus prevented, and the metal is allowed to
drop behind the riffles, where it accumulates, while the lighter particles or waste
matter continue their passage along the riffle plate until they are discharged onto
the chute a, from which they pass to the concentrating chamber a¹³, from which
they are discharged from time to time, or they may pass onto a carrier belt to be
carried out of the apparatus.
I do not confine myself to the construction and arrangement of parts, as shown
and described in Figures 1 to 6, as they may be greatly varied without departing
from the spirit of my invention.
my
invention
Referring now to Figures 7 to 16, illustrative of the second part of
relating to working river bottoms: Figure 7 illustrates an ore washer, concentrator
or amalgamator arranged on a scow or the like, and Figure 14 is a similar view
illustrating several such arranged in series, while Figure 15 shows the same arranged
on a truck; Figure 16 also showing the apparatuses in series, with means for
feeding the ore thereto and conveying the waste matter away. In these figures
indicates the force pump or pumps. I will first describe the river-bottom sweeping
devices illustrated in Figures 7 to 13, and would here state that a dredger, as
shown in Figures 14 and 15, may be combined with the sweeping devices. is the
sweeper and recoverer, supported on wheels, and containing a rotating brush 62,
operated by a water motor 63, Figures 7 and 11. In rear of brush 62 is an inclined
automatically adjustable apron 6 leading to a screen 6, Figure 8, that covers a
receiving chamber 6° having inflow b', the suction pipe being connected with the
sweeper case at 68, Figure 8, while motor 63 is connected by pipe 6° with pump 610.
The brush and apron 6 are weighted or otherwise induced to adjust themselves
to the inequalities of the surface swept over, Figure 13 showing an edge view of
said apron.
When the sweeper is at work the water entering chamber or pocket 66 rises
through screen 6 and keeps the material swept over the plate and screen in a
state of agitation, such material being drawn up by pump 6 and discharged into
a washer, concentrator or amalgamator. The operation of sweeping may be
assisted by forcing jets of water in front of the brush 62 through nozzles
Figure 12. Instead of the pocket 1, Figure 8, the suction-discharge duct of the
Sweeper may be provided with one or more pockets, Figure 12; in either case the
pockets are destined to receive the heavier particles of metal that separate from
the ore or gangue. The sweeper may be dragged along the river bottom by hand
or in any other desired manner.
Referring now to Figures 14 to 16, which illustrate a system of washing or

page_text: concentrating ores or gangue: c, c', care washers, concentrators or amalgamators,
which are preferably of one or the other constructions hereinafter to be described.
Each of said apparatuses has its own feed-pipe and suction-discharge pipe, the
latter conveying the material discharged from one apparatus into the next
succeeding, except the last apparatus of the series, a return water tube c being
provided for the return of a part of the water discharged, to the apparatus from
which it was discharged. The vessels c, c', Figure 15, are provided with overflow
pipes c, which may lead to an amalgamator c, or to a return pipe c from the last
vessel 3 of the series, (see also Figure 16,) which pipe returns to the receiver c',
having a float valve ca for the mouth of supply pipe c leading to the first
vessel c of the series, the water of the latter being, therefore, repeatedly used with
a view to economy when the apparatus is used in localities where water is scarce,
In
said return pipe being of course dispensed with in working river bottoms.
Figure 16 the digger co is supposed to be distant from the apparatus, said
digger discharging into a conveyor c" that feeds the ore to the first apparatus c of
the series, and c¹ is a conveyor that conveys the waste material away from said
apparatus.
It is obvious that by arranging the washers, concentrators or amalgamators in
series, a maximum quantity of metal is obtained with a minimum quantity of water
when the latter is scarce.
The appliances described in reference to Figures 7 to 16 may be greatly varied
in their construction, and I do not confine myself strictly to the described
construction.
Figures 17 and 35 illustrate the third part of my invention, which relates
more particularly to the mode of passing ore or gangue over amalgamated plates
with a view to preventing the rubbing off of the amalgam, or the passing of such
ore over the surface of a body of mercury, with a view to keeping said surface clean
and bright.
The essential feature of this invention consists in depositing the ore upon the
amalgam plate or mercury surface, propelling the same to a distant point, and then
removing the waste matter by suction; Figure 17 shows the invention in its
simplest form, d indicating a revoluble amalgam plate within a vessel d', and (2
and d³ are the feed and suction-discharge pipes, respectively, located diametrically
opposite each other above an amalgam plate. The feed pipe is preferably
provided with an adjustable scattering plate d. It will be noted that the material
is dropped in a more or less scattered condition onto the amalgam plate d, said
material having no motion of its own, and is carried by the plate to the discharge
pipe d³, which lifts the waste matter vertically off the said plate, so that there is no
rubbing or scratching, and as the material is fed in a dispersed condition into a
body of water, or together with the water, the metal particles are free to descend
to and amalgamate with the plate in advance of the waste material. Hence, large
quantities of ore can be rapidly passed through the apparatus with corresponding
efficient concentration of metal.
Figure 18 shows another form of the last described type of apparatus, in which
the feed and discharge pipes are revolved instead of the vessel, or the amalgam
plate, as in Figure 17. The vessel d', which here contains a body of mercury, has
a jarring motion imparted thereto for the purpose of agitating or scattering the ore
as it drops onto the body of mercury from the feed pipe d², the ore being first
screened in a screen d', from which it is fed to a receiver d' and thence to vessel d'.
The jarring motion is imparted to the vessel d', for instance, by a striker bar
reciprocated in any suitable manner, an elastic buffer de being provided for the
vessel to strike against. In this construction the feed and suction-discharge
pipes, d', d³, are revolved in vessel d' through the medium of a belt d' working on
pulley secured to the suction-discharge, to which the receiving vessel do and its
feed pipe dare rigidly connected.
a
In Figures 19 to 32 I have shown other forms of ore washers, concentrators or

page_text: amalgamators, by means of which the third part of my invention
carried out.
.
can be
In Figure 19 1 have also shown a revoluble mercury containing vessel or pan d,
provided with a central conical hub e to give the pan a trough shape, a depending
plate e, overlapping the edges of the pan, being provided. The outlet of the feed
pipe is here shown some distance above the pan d', so that the ore may have a
drop of a considerable distance, while the inlet of the suction-discharge pipe d³ is
close to the surface of the mercury in said pan d, which latter is provided with a
discharge plug e', the vessel d' having an outlet closed by a cover e for drawing
off the amalgam after its discharge from pan d. In Figure 20 the shaft to which
the pan d is secured is hollow, and is provided with a drip cock e¹ and an opening e
communicating with pan d, for drawing off the amalgam. In Figure 21 this is
effected by a pipe e, while the pan d is suspended from a bevel gear e' revolved by
a pinion e, while in Figure 22 the pan is revolved by a counter gear, having
alternate long and short teeth, so as to jig or shake the pan, a suitable roller
bearing e, properly cushioned, being provided to receive the shocks and prevent
the disengagement of the gearing. This jigging motion may also be obtained by
varying the depth of alternate teeth of bevel gear e', as shown in Figure 23.
The provision of a stationary vessel containing water supplied thereto, or fed to
feed pipe or chute d², or by a separate supply pipe having regulating valve,
Figures 19, 21 and 24, and a moving mercury pan or amalgam plate, admits of
using any desired depth of fall of ore through the water to the body of mercury f³,
and the deeper the water the greater the extent of fall, and the greater the fall
within serviceable limits the greater the velocity of descent of the metal particles
to the mercury, relatively to the lighter or waste material, so that such metal
particles are amalgamated before said lighter material reaches the surface of the
mercury. The use of a deep stationary body of water with a revoluble pan requires
less force than if the vessel d¹ were rotated.
Figures 24, 25 and 26 show a more complete and preferred form of apparatus of
the type under consideration, and from an inspection of the said figures of drawings
the operation will be readily understood. The vessel d' has on one side a vertical
partition 2, see also Figure 32, on one side of which is located the discharge d³
and on the other the feed d². This admits of the discharge being located as close
to the feed as possible without subjecting any of the incoming material to the
influence of the discharge, and a longer distance of travel is provided in vessel d¹
or pan d before the material reaches the field of force of the discharge. The edges
of the partitions f2 are provided with packing flaps f³ for sealing the feed side from
the discharge side of vessel d¹.
To avoid the heaping up of the material fed to the apparatus, the upper stratum
of the water is caused to circulate, thereby carrying said material from the feed to
the discharge. To this end the partition is cut away to the desired depth at its
upper end f, forming an opening for the feed chute d² so as to discharge above the
level of the water, at a tangent or otherwise. This causes the upper portion of
the water to circulate for carrying the ore around away from the place of its
deposit. The depth of circulation is controlled by the extent of the opening in
partition f, and if desired a suitable valve or gate f', Figure 27, may be provided
for regulating the depth of such circulation. Below such circulating water the
body of water in vessel d¹ is quiescent, and below the latter the moving or rotating
mercury pan d is located.
To prevent discharge of metal particles, a downwardly inclined shed or chute fo
Figure 25, is provided at the discharge end of vessel d' This shed may be in one
piece or in sections, the section f' being attached to and moving with partition f
when it is adjustable to and from the discharge. The water supply pipe ƒ has a
nozzle fº (see also Figures 29 and 30) adjacent to the discharge d³ so as to
loosen, agitate and wash the waste material on the surface of the mercury fas
said material approaches the suction-discharge.
adjusting mechanism for partition f² may be used.
Any suitable mounting and
To assist the top circulation of

page_text: water a jet pipe or pipes ƒ", Figure 28, may be located close to the discharge enu
of the feed chute d².
It will be noted that the ore drops in a scattered state into a circulating body of
water wherein it is further scattered, then descends through a comparatively deep
body of quiescent water, so that the metal particles have time to reach the mercury
in pan d before any waste material reaches the same. On the other hand, the waste
material, before being taken up by the suction-discharge is first again thoroughly
washed by the water coming through nozzle f, thereby removing any metal
particles that may still adhere to the waste, the weight of the deep body of water
exerts a rubbing action thereon and keeps the surface of the mercury f¹ always
bright, and further produces a rubbing, rolling or riffling action, thereby mixing
the mercury for presenting a constant new surface, and for effecting a continuous
pressing of the metal particles into the mercury, The suction pump instead of
being located outside of vessel d', as heretofore described, may be located within
the body of water therein, as shown in Figure 32, thereby dispensing with the usual
appliances for priming or charging the pump preparatory to starting the same,
while the vacuum lift of the pump is minimized, thereby diminishing the cost of
the plant and the running expense.
Motion may be imparted to pan d in any
suitable manner, as by a handle bar 10 on shaft of said pan, Figures 24 and 25,
or otherwise.
In Figure 33 I have shown an arrangement of jet nozzle or nozzles, g, located
below an arresting plate g' hinged so as to float on the surface of the mercury so
as to bring the ore to a comparative state of rest before passing to the surface of
the mercury, thereby breaking the force of descent or feed, the ore being propelled
across the mercury surface by said jet or jets of water, which also divides
comminutes the ore to more effectually free the metal particles.
suction-discharge d³ has a rearwardly extending chute g² and a closed forward end.
This chute admits of the propulsion of the ore across the surface of mercury after
said ore has passed out of the influence of the jet or jets.
or
The
In order to prevent the mercury being drawn into the suction discharge ³, the
latter may have a suitably inclined apron 3 projecting from the outlet thereof, as
shown in Figure 34, or the suction pipe may have a vertically adjustable arresting
plate g, Figure 35, secured thereto, said plate lying below the zone of greatest
suction force, i.e., below the inlet of the discharge pipe, and resting on or imme-
diately above the body of mercury on the bottom of the vessel d', or in a moving
vessel d', or in said body of mercury f¹, so as to displace the same, and if desired,
the plate may be provided with adjustable sides 9³, Figure 35, so as to vary
the thickness thereof.
In the working of placer gravel in accordance with the fourth part of my invention,
the black-sand so difficult to remove from the metal may be magnetically removed
by interposing a magnet or magnets between the feed and suction-discharge, and
providing means for cleaning the magnets of magnetic material at short intervals
on its way from the feed to the suction-discharge, and in order to reduce the
suction force to a minimum, a magnetic field may be arranged adjacent to the said
suction-discharge. One form of apparatus embodying the above principles is shown
in Figure 36. ' is the receiving vessel having an inclined bottom and a pocket h,
the feed pipe d being preferably provided with a valve 2 for regulating the feed,
while the suction-discharge d³ has a ledge or shelf (33 on which is a magnet h', one
or more magnets 2 being interposed between said magnet and the feed pipe d²,
said magnets 2 having preferably a common pole plate h³, which constitute
the top of vessel d'; it is obvious that as the auriferous sand is propelled upwardly
towards the suction-discharge the black-sand is alternately attracted and released
by the magnets 2, thereby holding said sand in suspension, the same being repeated
as it reaches the inlet of the suction-discharge, thereby minimizing the suction
force necessary to discharge the sand from the apparatus, and facilitating the
separation of the metal particles therefrom, which fall onto the inclined bottom and
descend by gravity into pocket h, from whence they are removed from ti.ne to
may
B

page_text: time. The magnets are included in the circuit of a source of electricity, which
also includes a circuit breaker h for alternately making and breaking the circuit
through the magnets; or alternating currents may be passed through the magnets
for a similar purpose.
h
The magnet may be dispensed with, Figure 38, and instead of a rigid bottom
and a jet propelling device, a movable amalgamating surface may be employed, as
a mercury containing vessel d, Figure 37, or an endless carrier, or a jigger bottom /°,
Figure 39, or an endless travelling belt e, Figure 40. When a jigger bottom or
reciprocating riffle plate is used, the separation of the black sand is most effectually
accomplished, inasmuch as at each forward movement of the plate or bottom the
auriferous sand is thrown upward and forward and scattered in the water, enabling
the metal particles to more readily fall behind the riffles, and the magnets to more
readily attract the sand, as first herein explained.
Under some conditions of service it may be desirable to discharge the black-sand
separately from the other waste material, and instead of fixed magnets, traveling
magnets may be employed, combined with mechanical clearers or wipers. It is also
desirable in working piacer gravel to separate the lighter from the heavier waste
material for the purpose of recovering the float gold.
In Figure 41 I have illustrated a revoluble magnet or magnets k adjacent to the
suction discharge d³ fabove and proximate to the surface of mercury, an auxiliary
water-supply pipe k being provided, and is a revoluble brush for clearing the
magnetic material from the magnet k. In Figure 42 I have shown traveling
magnets combined with a wiper brush k², the black-sand being discharged
separately into chute *, the auxiliary water-supply pipe being arranged over the
feed chute d².
Figures 43 and 44 show a more complete apparatus of the type shown in
Figures 41 and 42, an additional suction-discharge pipe d being arranged between
the feed and main suction-discharge, a plurality of revoluble magnets being
arranged between the auxiliary suction-discharge and the main suction-discharge,
and a traveling magnetic separator k³ is arranged proximate to the main suctior-
discharged for purposes explained.
In working certain ores it may become desirable or necessary to pass the black-
sand or the lighter waste material containing the float gold to another amalgamator
for the separation of metal particles yet contained in the sand, or the float gold in
the lighter waste materials. In order that this may be thoroughly effected I
provide, according to the fifth part of my invention, an amalgamator of such
construction that the material, together with water flowing therethrough, will be
divided into a series of thin streains and brought into contact with amalgamating
surfaces arranged in gangs. Such an apparatus is shown in Figures 45 to 47, the
gangs of amalgamating plates m being contained in suitable casings m' alternately
inclining in opposite directions and opening into collecting pockets m², the last
pocket of the series having a discharge pipe m³ connected therewith. The pockets
also contain a body of mercury m³, Figure 47, for the amalgamation of such metal
particles as may escape from the plates. I also provide means for adjusting the
inclination of the several gangs of plates either separately, as shown in Figure 47,
or collectively, as shown in Figure 45. The adjustability of the gangs of
amalgamating plates is, however, not indispensable, and when the requirements of
service do not demand this I prefer to construct the apparatus as shown in Figure 48,
in which a cheap and simple construction is shown, the entire apparatus being
constructed of cylindrical or pipe sections provided with bolt flanges for uniting
them. The apparatus consists of cylindrical uprights n in sections, and cylindrical
casings n bolted to said uprights, the bottom n² of the upper sections being below
the inlet of the two upper casings n', whereby the pockets above referred to are
formed. Each pocket is provided with a discharge or purge cock or valve n', an
auxiliary purge cock n' being provided for one of the lower sections for the purpose
of drawing off most of the water before discharging the amalgam therein. Suitable
doors n are provided for the introduction of the amalgam plates.

page_text: From the description of my invention it will be clear that the apparatuses can
be variously modified in their construction without departing from the spirit of my
invention, and I desire it to be distinctly understood that I do not confine this
invention exclusively to constructions shown and described.
-
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. The method of separating metals from ore or gangue, which consists in placing
a layer or body of mercury in a vessel, depositing the ore adjacent to the surface
of the mercury, causing said ore to be scattered or disbursed above the surface of
the mercury and correspondingly propelled or conveyed from its place of supply to
a place of discharge distant from the former, for effecting a separation of the metal
from the ore without commingling the latter with the mercury, and then dis-
charging the gangue from said vessel, substantially as set forth.
2. The method of separating metal particles from black-sand (as it is conducted
over shaking riffle plates in water in placer gravel machines), which consists in
imparting to the black-sand repeated short advancing movements and suspending
or keeping it alive in the water at the termination of each such movement,
substantially as set forth.
3. In the art of working placer gravel, the method which consists in feeding the
material through a body of water onto an amalgamating surface and removing the
magnetic and non-magnetic constituents of said material separately from said
surface, substantially as and for the purpose set forth.
4. In the art of washing and concentrating ores, the method of maintaining the
black-sand particles of the ore in a scattered or diffused condition, which consists
in imparting to the ore repeated short advancing movements, and simultaneously
therewith repeatedly and successively magnetically condensing such sand particles
and scattering and diffusing them in the washer in advance of their discharge,
substantially as set forth.
5. The mode of washing and concentrating ores and maintaining the black-sand
particles in a scattered or diffused condition from the entry of such sand into the
washer until it reaches a suction-discharge for said sand, which consists in repeatedly
and successively magnetically condensing such sand particles and scattering or
diffusing them in the washer in advance of their discharge, and in again magneti-
cally condensing and then scattering or diffusing them in the vicinity of the inlet
to the suction-discharge, substantially as set forth.
6. The method herein described of washing and concentrating ore, which consists
in feeding the ore into a depth of still or quiescent water to admit of the metal
particles of the ore falling through the water faster than the waste matters, then
subjecting the metal particles and waste matters to the action of a moving body of
mercury at the termination of their descending movement, and then discharging
such waste matters, substantially as set forth.
7. The method herein described of washing or concentrating ore, which consists
in feeding the ore into a stratum or body of circulating or moving water, then
causing it to pass through a stratum or body of quiescent water beneath said
circulating water, and then subjecting it to the action of amalgamation, and then
removing the waste matter, substantially as set forth.
8. In a machine for working placer gravel, the combination of a stationary vessel
containing a body of water, a series of screens of different mesh one above the
other and inclining downwardly from their feed to their discharge ends, a corre-
spondingly inclined rifle plate beneath the lowest screen and moving with said
screens, and a discharge device for the waste material with or without a separate
discharge for the black-sand escaping from the riffle plate, substantially as and for
the purpose set forth, and as shown in Figures 1 to 6 inclusive.
9. The combination of a positively actuated sweeper separate from and actuated

page_text: independently of a positively actuated dredger, substantially as described, and
shown in Figures 7 to 12 inclusive.
10. The combination of a positively acting dredger, of a sweeper having
actuating mechanism separate from the dredger, which has mechanism for moving
it without moving the sweeper, substantially as described, and shown in Figures 7
to 13, inclusive.
11. The system herein described for separating metal from its ore and the pure
metal from the impure metal, substantially as set forth, and as shown in Figures 14
to 16, inclusive.
1
12. In au ore washing, concentrating and amalgamating plant having a series of
succeeding vessels, means for discharging the flow of gangue from said vessels and
returning part of the discharge to the vessel from which it was discharged,
substantially as set forth and shown in Figures 14 to 16, inclusive.
13. In combination with a stationary plant for separating metal from its ore,
and the impure metal from the pure metal, a conveyor for carrying the ore to
the plant and a conveyor for removing the gangue to a location distant from
the plant, substantially as set forth and shown in Figures 14 to 16, inclusive.
14. In an amalgamator, an amalgam plate, a feed device and a suction-
discharge device, said amalgam plate having motion relatively to the feed and
suction-discharge devices or vice versa, for the purpose set forth, and as shown
in Figures 17 and 18.
15. In an ore washer or concentrator, the combination of a stationary vessel
coutaining a body of water, a rotating mercury containing vessel in said stationary
vessel, a feed device, and a suction-discharge, substantially as set forth, and as shown
in Figures 19 to 32 inclusive.
16. In an ore washer or concentrator, a receiving vessel adapted to contain a
body of water, a partition f2, and an adjustable gate on said partition, substantially
as set forth, and as shown in Figures 19 to 32.
17. In an ore washer or concentrator, a receiving vessel having a suction-
discharge, and a feed device sealed from said suction-discharge, with or without
a shed or cover for the latter, substantially as set forth and as shown in
Figures 19 to 32.
18. In an ore washer or concentrator, a receiving vessel baving a feed device,
a suction-discharge, and a chamber enclosing inlet end of said suction-discharge,
substantially as set forth, and as shown in Figures 19 to 32.
19. In an ore washer or concentrator, the combination of a mercury containing
vessel, a feed device and a suction-discharge device located at a distance apart,
a jet tube or tubes for propelling the ore across and adjacent to the surface of
the mercury from the feed to the discharge, substantially as set forth, and as
shown in Figure 33.
20. In an ore washer or concentrator, the combination of a vessel adapted to
contain mercury, a suction-discharge pipe for said vessel, and a mercury cover
or arresting plate located adjacent to the inlet end of the suction-discharge pipe,
substantially as set forth, and as shown in Figures 34, 35 and 35.
21. In au ore washer, concentrator or amalgamator, the combination of a receiving
vessel, a suction-discharge therein, a magnet at or near the inlet of said suction-
discharge, and circuit connections including a source of electric supply for said
magnet, substantially as set forth, and as shown in Figures 36 and 37.
22. In an ore washer or amalgamator, the combination of a receiving vessel,
a shaking or jigger bottom for or in said vessel, transverse riffles on said bottom,
a feed device and a suction-discharge for said vessel, one or more magnets
located between the feed and discharge devices, and above and adjacent to said
bottom, and circuit connections with a source of electrical supply for said magnets,
substantially as set forth, and as shown in Figures 38, 39 and 40.
23. In an ore washer and amalgamator, the combiuation with a receiving
vessel containing an amalgamating surface, and a superposed body of water, a

page_text: feed device, a suction-discharge distant from said feed device, and means for
moving the ore from the feed device to said suction-discharge; of an auxiliary
suction-discharge located between the feed and main suction-discharge, for the
purpose set forth, and as shown in Figures 41 to 44, inclusive.
24. In an ore washer or amalgamator, the combination with a receiving vessel
containing a body of water, a feed device, a suction-discharge distant from said
feed device, aud a movable amalgamating surface immersed in the water, said
surface adapted to convey the ore fed thereto to the suction-discharge, of revoluble
magnets between the feed and suction-discharge and adjacent to the inlet of the latter
and to the amalgamating surface, and means for clearing the said magnets of
magnetic material adhering thereto, substantially as and for the purpose set forth,
and as shown in Figures 41 to 44.
25. In an ore washer or concentrator, the combination of a receiving vessel,
a feed device, a rotating or traveling amalgam surface, a suction-discharge and
a magnetic discharge device, substantially as set forth, and as shown in Figures 41
to 44 inclusive.
26. In an amalgamating device having a flow for passing the ore or gangue
through the amalgamator, gangs of chutes in the path of said flow for dividing
the flow into a number of thin streams, and pockets at the ends of said gangs
for reuniting said streams in a single flow, substantially as set forth, and as
shown in Figures 45, 46 and 47.
27. The combination with chamber, of the gangs of alternately directed
casings m', and actuating devices for varying the degree of their inclination,
substantially as set forth, and as shown in Figures 45, 46 and 47.
28. The combination of tubular casings having edge flanges and a catch
pocket bolted to said flanges and common to a series of plates in said casings,
substantially as set forth, and as shown in Figure 48.
29. The combination of the sectional tubular uprights, as n, n, having inlet
and outlet ports, and tubular casings as n', n', having their opposite ends
respectively connected with the inlet and outlet ports of said uprights, and a
cross partition below one of the inlet ports of each upright, substantially as set
forth, and as shown in Figure 48.
30. In an ore washer and amalgamator, the combination of sectional tubular
ends n, n, having draw-off cocks, removable caps or covers, and inlet and outlet
ports, tubular casings n', joiuing said ends, and gangs of catch-plates m, in
casings n', substantially as set forth, and as shown in Figure 48.
Dated this 13th day of November 1894.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.