IMPROVEMENTS IN THE SEPARATION OP COPPER AND OTHER METALS FROM SILVER AND GOLD, THE SAME BEING APPLICABLE TO OTHER METALLURGICAL OPERATIONS
Year: 1868

page_text: LETTERS PATENT to Richárd Pearce, of Swansea, in the County of
Glamorgan, for the Invention of "IMPROVEMENTS IN THE SEPARATION
OP COPPER AND OTHER METALS FROM SILVER AND GOLD, THE SAME BEING
APPLICABLE TO OTHER METALLURGICAL OPERATIONS."".
Sealed the 19th February 1869, and dated' the 16th October 1868.
PROVISIONAL SPECIFICATION left by the said Richard Pearce at
the Office of the Commissioners of Patents, with his Petition, on
the 16th October 1868.
I, RICHARD PEARCE, of Swansea, in the County of Glamorgan, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE SEPARATION OF COPPER AND OTHER METALS FROM SILVER AND GOLD, THE
SAME BEING APPLICABLE TO OTHER METALLURGICAL OPERATIONS," to be as
follows:-
This Invention relates especially to the purification of silver which has
been precipitated from its sulphate, nitrate, or chloride by copper, but is
also applicable to the analogous treatment of gold and other metals;
but in this Specification the treatment of silver is herein-after referred

page_text: to, as the application of the present Invention to gold and other metals,
and for the separation of copper, iron, and other heavy impurities from
tin ore, and also in the manufacture of sulphate of copper and in other
analogous operations, will be well understood by persons conversant with
metallurgical processes.
The impure silver is placed on a filter in a boiler; water is added,
together with a small quantity of sulphuric acid, the proportion of the
latter necessarily varying with the amount of copper present, as will be
.well understood; steam with atmospheric air mingled therewith is then
admitted by means of an injecting apparatus; violent ebullition ensues,
and the copper becomes oxidised and is dissolved by the sulphuric acid.
Should the ebullition become too violent it may be checked by admitting
less air. After being boiled in this way for about two hours the solution
of sulphate of copper is drawn off, the silver stirred so as to make it
a little more granular, a fresh supply of water which has been slightly
acidulated with sulphuric acid is added, and the mixture is then boiled
for about one hour. The solution is afterwards drawn off and the silver
carefully washed with clean water. The silver when dry has only to be
melted in crucibles for fine silver, refining in the usual way by means of
lead being quite unnecessary.
In the event of a little silver passing into solution towards the close of
the operation of boiling, plates of copper may be introduced into the
boiler for a few minutes and the air excluded; any traces of silver that
may have passed into solution will thus be precipitated.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Pearce in the Great Seal Patcut Office
on the 9th April 1869..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
PEARCE, of Swansea, in the County of Glamorgan, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 3
Letters Patent, bearing date the Sixteenth day of October, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Richard Pearce, Her special licence that I,

page_text: the said Richard Pearce, my executors, administrators, and assigns, or
such others as I, the said Richard Pearce, my executors, administrators,
and assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN THE SEPARATION
OF COPPER AND OTHER METALS FROM SILVER AND GOLD, THE SAME BEING
APPLICABLE TO OTHER METALLURGICAL OPERATIONS," upon the condition
(amongst others) that I, the said Richard Pearce, my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Richard Pearce, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement, that is to say:-
My said Invention relates especially to the purification of silver which
has been precipitated from any of its salts, such for example as sulphate,
nitrate, or chloride, by copper, and in the separation of copper from
compounds of copper and silver, but it is also applicable to the analogous
treatment of gold and other metals. In this Specification, however,
the treatment of silver is herein-after referred to, as the application of my
said Invention to gold and other metals, and for the separation of copper,
iron, and other heavy impurities from tin ore, and also in the manu-
facture of sulphate of copper and in other analogous operations, will be
well understood by persons conversant with metallurgical processes.
The impure silver, or compound of silver and copper, is placed on a
perforated disc in a boiler. Water is added, together with a small
quantity of sulphuric acid, the proportion of the latter necessarily
varying with the amount of copper or other impurities present, as will
be well understood. Steam with atmospheric air mingled therewith is
then admitted by means of any suitable injecting apparatus; violent
ebullition ensues, and the copper becomes oxidised and is dissolved by
the sulphuric acid. Should the cbullition become too violent it may

page_text: be checked by admitting less air. After being boiled in this way for
about two hours the solution of sulphate of copper is drawn off, the
silver stirred so as to make it a little more granular, a fresh supply
of water which has been slightly acidulated with sulphuric acid is added,
and the mixture is then boiled for about one hour. The solution is
afterwards drawn off and the silver carefully washed with clean water.
The silver when dry has only to be melted in crucibles for fine silver,
refining in the usual way by means of lead being quite unnecessary.
In the event of a little silver passing into solution towards the close
of the operation of boiling, plates of copper may be introduced into the
boiler for a few minutes and the air excluded. Any traces of silver that
may have passed into solution will thus be precipitated.
Having thus described and ascertained the nature of my said
Invention, and the manner in which it is to be performed, I would
observe in conclusion that what I consider novel and original, and
therefore claim as constituting the Invention secured to me by the
said herein-before in part recited Letters Patent are, the processes for
effecting the purposes aforesaid, substantially as herein-before described
and set forth, or any mere modifications thereof.
In witness whereof, I, the said Richard Pearce, have hereunto set
my hand and scal, this Sixth day of April, in the year of
our Lord One thousand eight hundred and sixty-nine.