An Improved Gold Saving and Amalgamating Machine.
Year: 1896

page_text: Date of Application, 23rd Nov., 1896-Accepted, 6th Feb., 1897
An Improved Gold Saving and Amalgamating Machine.
We, GUSTAF DILLBERG of 77 Elizabeth Street, Sydney, New South Wales,
Electrician, and WILLIAM WALKER of 77 Elizabeth Street, aforesaid, Consulting
Engineer do hereby declare the nature of this invention to be as follows:-
This invention has for its object the construction of a mechanical contrivance in
which, by the aid of mercury, the free gold contained in pulverized or disintegrated
material, such as sand, gravel, wash dirt, tailings and the like, which we herein will
call material, may be saved by amalgamation.
In existing gold saving appliances, where mercury is used for the purpose of
picking up the gold by amalgamation, the mercury in some cases is caused to
adhere to copper or other suitable metal plates, over which the material in
conjunction with water travels, when the particles of gold are calculated to sink to
the mercury by gravitation and be amalgamated therewith, and thus saved, but as
many gold particles are very light and very thin, instead of sinking to the mercury,
they are carried away on the top of the water as float gold, or with the material,
thus a large percentage of gold is lost. The material in passing over the mercury
plates must necessarily cause a rubbing against the mercury surface and detach
particles therefrom (generally mercury with which gold is already amalgamated) thus
carrying them away to waste. Other methods of saving the gold particles by
mercury, consist in forcing the mercury through the material or the material
through the mercury, or by as intimately as possible, intermixing the material and
the mercury to cause the gold particles to come into contact with the mercury and
thus be amalgamated. This operation generally causes the mercury to become
floured, that is, divided into numerous minute particles or globules, of which more
or less is carried away by the material, thus causing a considerable loss, both of
gold and mercury.
When the material can be caused to pass through the mercury without churning
it, or dividing its bulk into minute particles, the operation will naturally become
perfect, as the gold particles will be retained by amalgamation and the remainder
of the material not capable of amalgamation will leave the body of the mercury
and collect on the surface, owing to the difference of specific gravity, and may be
removed without any possibility of its containing any free gold. This effect is
obtained in this invention by the aid of centrifugal force.
To accomplish this object, we employ a shallow pan of iron or other suitable
material, (with which mercury has no affinity), of special construction, but to
facilitate explanation, drawings are annexed.
Fig. 1 being a vertical section and Fig. 2 a plan.
a is a shallow pan of non-amalgamating material, such as wrought or cast-iron,
the bottom of which is marked b. c is the side of the pan, preferably perpendicular,
but which may curve outwards. At the junction of b and c the pan is curved so
that mercury moving along 6 towards c may rise up the side c without rebounding
from c, if its velocity is sufficiently great. d is an internal lip or ring, forming
with b and c an annular space, necessarily shallow, as d projects but a short
distance. d may be straight, curved downwards, or otherwise bent, but must be at
such an angle that when the pan a is in a horizontal position d is also in a
horizontal position, or dipping towards b. Inside a and near the bottom b is a

page_text: ringe rigidly attached to 6 by studs or bolts f, or by other suitable means, leaving
an open space between b and e, and between e and c. The ring e acts as a cover
to b, and between e and b the material is guided towards c. The outer edge of e
may be curved as shewn. One is a removeable cover e', to enable material to be
removed from the pan when not in operation, it is so arranged that though easily
detachable from e it is firmly held to it by means of lugs, and revolves with it when
in operation. In the centre of e¹ but detached from it is placed a funnel or tube g
which is secured to the framing h and through which the material to be treated is
introduced into a. The pan a is centred on and rigidly secured to the spindle i by
any known means, which latter rests in a step ; in the bracket k. On the spindle i
is the bevel wheel 1, which gears with the bevel wheel m on the spindle n, on which
is the pulley o, the latter being driven from the pulley p by hand or other motive
power. We do not confine ourselves to the driving gear shewn, as it is evident
that any form or design of pulleys or gearing may be used to revolve the pan.
The bracket k is bolted or otherwise secured to the framing h, which may be of
wood or any other suitable material or materials. The metal apron g surrounds
the pan, and the lower gear is covered by a shield r, to protect the bearings
from dust, and which also acts as a chute for the waste material. A cock
may be arranged in the bottom of the pan, to enable it to be emptied of its
contents.
To operate the machine, the procedure is as follows:-
In the pan a is placed a requisite amount of mercury to cover the side to a
thickness previously determined upon. By actuating the driving gear, the pan a
is caused to revolve until sufficient speed has. been obtained to make the mercury x
form a circular wall in front of the side c, which mercury is prevented from being
thrown from the pan by the lip d. The materials to be treated is now allowed to
flow into a through the funnel g whilst a is revolving at the requisite speed. On
reaching the bottom b, the material is thrown with great force between band e
towards c, owing to the centrifugal force, follows to a certain extent the curve
between b and c and penetrates the mercury. Any particles of free gold will be
picked up by the mercury and retained, the remainder of the material being of
lighter specific gravity than the mercury, and not capable of amalgamation, will
rise in same, whilst at the same time, owing to the joint action of specific gravity
and centrifugal force, the material & will take up a position on the free surface of
the mercury.
The centrifugal force will then force the materials to rise until it reaches the
lip d, when it will be discharged from the machine against the apron q, and falling
on the chuter is removed by any suitable means.
Any tendency to churning of the mercury by being bombarded continuously
by the materials, is counteracted by the centrifugal force (as any particles which
may become separated are immediately reunited) which at the same time ejects
any impurities in the mercury of a less specific gravity, whilst anything of equal or
greater specific gravity will be retained and stored, even if not amalgamated,
thus grains of platinum will be retained between the wall of mercury and the side
of the pan.
When the machine stops, the mercury and its contents naturally
fall to the bottom of the pan, and the amalgam &c. may be taken out by removing
the cover e¹.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In a machine for saving gold by amalgamation, a shallow pan, having an
inwardly projecting lip at the top, and a curved incline at the bottom, between the
junction of the side and bottom, so that in the covered annular space thus formed,
mercury may be held perpendicularly in a circular wall, by means of centrifugal
force, substantially as herein set forth and shewn on the drawings.
2 In a machine for saving gold by amalgamation, a shallow pan such as a, in

page_text: combination with a ring such as e, secured to the bottom of said pan, substantially
as and for the purpose herein set forth.
3. In a machine for saving gold by amalgamation, a shallow pan such as a, in
combination with the ring e and cover e', substantially as and for the purpose herein
set forth.
4. In a machine for saving gold by amalgamation, a shallow pan such as a
centred on the spindle i, in combination with the ring e, cover e¹, and funnel g,.
substantially as described and shewn on the drawings.
5. In a machine for saving gold by amalgamation, a shallow pan such as a, in
combination with liquid mercury held perpendicularly in a circular wall between
the lip d and bottom 6 of the pan, by centrifugal force, when the pan is revolved at
a sufficiently high rate of speed, substantially as and for the purpose herein set
forth.
Dated this Nineteenth day of October 1896.
GUSTAF DILLBERG.
W. WALKER.