A NEW METHOD OF TREATING REFRACTORY ORES OF SILVER
Year: 1872

page_text: LETTERS PATENT to Jasper Henry Selwyn, of Gloucester Crescent,
Hyde Park, in the County of Middlesex, Captain, Royal Navy, for
the Invention of "A NEW METHOD OF TREATING REFRACTORY ORES OF
SILVER."
PROVISIONAL SPECIFICATION left by the said Jasper Henry Selwyn
at the Office of the Commissioners of Patents, with his Petition,
on the 27th May 1872.
I, JASPER HENRY SELWYN, of Gloucester Crescent, Hyde Park, in
the County of Middlesex, Captain, Royal Navy, do hereby declare the
nature of the said Invention for "A NEW METHOD OF TREATING REFRACTORY
ORES OF SILVER," to be as follows:-
The chief object of this Invention is to extract silver from certain
refractory ores of silver to which the processes now commonly employed
are for economic reasons inapplicable.
The class of silver ores to which my Invention applies possesses a
large per-centage of lime, the presence of which enables me in many

page_text: cases to accomplish the disintegration necessary in order that the silver
may be attacked by the chlorine without the necessity of stamping or
other mechanical means of comminution.
In carrying out my Invention I boil the said ores in large quantities
in wooden, earthenware, enamelled metal, or other suitable vats con-
structed for the purpose (by the use of steam, superheated or otherwise,
or other heating process) in a concentrated solution of common salt or
in a chlorine solution. After boiling for a given time I obtain a clear
metallic solution, which is then run into tanks containing scrap iron or
copper, or other suitable precipitant, and the precipitation of the silver
and other metals contained in the ore will then take place, or the
precipitation may be effected by simple dilution or other well-known
means.
In certain cases I use hydrochloric acid with the solution of common
salt, and this may be added per se, or be generated in the solution by a
stream of chlorine gas.
The ores may be calcined previously to boiling either with or without
common salt or other suitable reagent in order to get rid of combinations
unsuitable to the boiling process.
The metals collected by precipitation in the tanks can be treated by
any of the ordinary methods for bringing them into a commercial
condition.
By the above process I obtain a much higher per-centage of the
precious and other metals existing in refractory ores than has heretofore
been secured, and owing to the small cost of the process I am enabled
to treat profitably ores that have hitherto been considered commercially
worthless.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JASPER
HENRY SELWYN, of Gloucester Crescent, Hyde Park, in the County of
Middlesex, Captain, Royal Navy, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of May, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Jasper Henry Selwyn, Her special licence
that I, the said Jasper Henry Selwyn, my executors, administrators, and
assigns, or such others as I, the said Jasper Henry Selwyn, my execu-
tors, 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 "A NEW METHOD
OF TREATING REFRACTORY ORES OF SILVER," upon the condition (amongst
others) that I, the said Jasper Henry Selwyn, my executors or admi-
5 nistrators, 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 Jasper Henry Selwyn, 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) : —
The chief object of this Invention is to extract silver from certain
refractory ores of silver to which the processes now commonly employed
are for economic reasons inapplicable.
The class of silver ores to which my Invention applies possesses a
large per-centage of lime, the presence of which enables me in many
cases to accomplish the disintegration necessary in order that the silver
may be attacked by the chlorine without the necessity of stamping or
other mechanical means of comminution.
In carrying out my Invention I place the ore in wooden, earthenware,
enamelled metal, or other suitable vats constructed for the purpose, and
by the aid of steam, superheated or otherwise, or by any other means of
licating, I boil the ore in a concentrated solution of common salt, to

page_text: which is added hydrochloric acid, or into which a stream of chlorine gas
may be discharged during the continuance of the boiling process.
The ores may be calcined previously to boiling either with or without
common salt, or other suitable reagent, in order to get rid of combina-
tions unsuitable to the boiling process.
The proportions of materials which I have found to give a good
result in carrying out my Invention are, salt, one and a half parts by
weight; hydrochloric acid, one and a half parts; water, two parts.
These proportions will serve for one part by weight of the calcined silver
ore. When I use chlorine gas in the place of the muriatic acid the
same proportions of salt and water are employed, and the chlorine is
of course generated in a separate vessel. The boiling of the ore will in
general require to be maintained for one hour, by which time a clear
metallic solution will be obtained. I run this solution off into a tank,
vat, or other suitable vessel, and I effect the precipitation of the metal
by passing sulphuretted hydrogen gas into the solution.
Instead of the proportions of materials above stated I have found
that a good result may be obtained by boiling the silver ore previously
chloridized by heating with salt in a concentrated solution of salt and
muriatic acid, the bath being composed of salt, two parts; water, two
parts; and muriatic acid, one and a half parts.
The most effective way of applying the chlorine gas in conjunction
with the solution of common salt as described is when the gas is in the
nascent state. In order to effect this I add manganese to the solution
of common salt and muriatic acid, and at the same time I increase the
quantity of acid. The proportion of manganese which I have found to
answer is one part to the quantity of materials stated, with three
additional parts of hydrochloric acid. By the reaction of the manganese
upon the hydrochloric acid chlorine gas is generated, and in this form
acts more rapidly and effectively than when it is simply passed into the
boiling solution.
The metals collected by precipitation in the tanks can be treated by
any of the ordinary methods for bringing them into a merchantable
condition.
By the above process I obtain a much higher per-centage of the
precious and other metals existing in refractory ores than has heretofore
been secured, and owing to the small cost of the process I am enabled

page_text: to treat profitably ores that have hitherto been considered commercially
worthless.
Having now set forth the nature of my Invention of "A New Method
of Treating Refractory Ores of Silver," and explained the manner of
carrying the same into effect, I wish it to be understood that under the
above in part recited Letters Patent I claim, subinitting refractory ores
of silver to boiling in a bath composed as above described, whereby the
contained metals will be recovered in the form of chlorides.
In witness whereof, I, the said Jasper Henry Selwyn, have here-
unto set my hand and seal, the Thirty-first day of July, in the
year of our Lord One thousand eight hundred and seventy-
two.