IMPROVEMENTS IN REFINING GOLD
Year: 1850

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66 Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Twenty-second day of August, in the fourteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Edward Newton, Her especial license, full power, sole
privilege and authority, that I, the said William Edward Newton, my exors,
admiors, and assigns, and such others as I, the said William Edward Newton,
my exors, adñiors, or assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein mentioned,.
should and lawfully. might make, use, exercise, and vend, within England,
Wales, the Town of Berwick-upon-Tweed, and in all Her Majesty's Colonies
and Plantations abroad, and in the Islands of Jersey, Guernsey, Alderney,
Sark, and Man, an Invention of "IMPROVEMENTS IN REFINING GOLD," being a
communication from abroad; in which said Letters Patent is contained a
proviso, obliging me, the said William Edward Newton, by an instrument in
writing under my hand and seal, particularly to describe and ascertain the
nature of the said Invention, and in what manner the same is to be performed,
and to cause the same to be inrolled in Her Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said in

page_text: part recited Letters Patent, as m and by the same, reference being thereunto
had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Edward Newton, do hereby declare that the nature of the said Invention
and the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof (that is to say):-
The Invention which has been communicated to me from abroad, and for
which I have obtained Letters Patent as aforesaid, relates to a novel and
improved method of separating silver and other impurities from gold bullion,
the same being an improvement in the art of refining gold for coinage and
other purposes.
In order that the nature and object of the present Invention may be
properly understood, I will describe so much of the methods heretofore known
and now usually practised, as is necessary for the purpose. The present mode
of refining gold bullion consists in part of the operation of quartation, as it is
called, that is, of melting and intimately combining with the gold bullion to be
refined, from two to three times its weight of silver. To extract this silver
together with that and all impurities originally contained in the gold bullion
itself from the mixed alloy of gold and silver, it requires that it should be
granulated, by pouring it while melted into water, and subsequently that it
should be digested, either in sulphuric acid concentrated to sixty-six degrees
Baumé at the boiling temperature thereof, costly platinum vessels being em-
ployed for the purpose; or the digesting operation may be effected by submit-
ting it to nitric acid of thirty-six degrees Baumé, at temperatures not lower
than two hundred and twelve degrees Fahrenheit, or the boiling point of
.water, fragile vessels of glass, porcelain, or earthenware being employed in this
case.
The chief objections to these methods are, first, the withdrawing of large
quantities of silver from use as circulating capital; second, the great labor,
expense, and delay attending the successive granulation, separation and rc-
covery from solution of that silver; third, the loss of interest; fourth, the
wastage of silver; fifth, the very high cost and expensive repairs of the large
platinum retorts required in the sulphuric acid process, and the frequent
breaking of the vessels used in the nitric acid process, attended with more or
less loss of the precious contents thereof.
The improvement and advantages in the art of refining gold attained by
the present Invention are, first, the comparative easy separation from gold
bullion of the impurities with which it is in combination without using silver
for quartation, and consequently preventing the waste of silver and the ne-

page_text: cessity of using costly apparatus; second, a great economy of time, labor,
and expense is effected; third, the saving of interest of capital sunk in carry-
ing on the operation of refining as conducted by the old processes; fourth,
the use of lower temperatures than in the usual methods, and the employment
of vessels of lead which are not subject to fracture; fifth, the rendering the
work of the refiner more simple, expeditious, and free from the necessity of his
constant attention, also less injurious to his health, and no longer a nuisance
to the neighbourhood, if conducted in densely populated places.
The nature of the present Invention consists in bringing gold bullion, con-
taining silver or other impurities, into a loose, divided, pulverulent, or spongy
state, texture, or disintegrated molecular condition, so that all the impurities
it may contain can readily be removed by acids. The obtaining of gold in
such a state, or reducing it from a compact to a disintegrated condition, so
that it may be attacked by acids, forms no part or object of the methods now
in use.
And it is this preliminary mechanical operation which gives to the
present improvement in the art of refining gold, the great advantage of dis-
pensing with the use of large quantities of silver, thus causing economy in
labour, time, and expense.
To enable those skilled in the art of refining gold bullion to understand and
use the present Invention, I will now describe its nature and operation :—
I may here mention, in the first place, that the gold bullion to be refined
may be of any quality. The first or preparatory operation is to make an
adulterated alloy or mixture by melting and mechanically stirring the gold
bullion with a sufficient quantity of zinc, usually two or three times the weight
of the gold bullion to be refined; and after the melted alloy has been well
stirred, it is granulated by pouring it into water according to the usual methods.
Secondly, the granulated alloy is treated in wooden vats, lined with lead,
with dilute sulphuric acid which removes the zinc employed for adulteration,
and leaves impure or argentiferous gold in a finely divided pulverulent or
spongy state, or in a disintegrated molecular condition. The hydrogen which
escapes during the operation should be conducted by wooden or other pipes
into the open air. In this second operation heat is not used or required, and
no more acid is employed than will combine with the quantity of that metal
used for adulteration and form sulphate of zinc; in other words, the acid is
used in atomic proportion.
The object, sought by the two operations just described, is only to operate
on the gold bullion in such a manner as to reduce it to a disintegrated or
spongy state, in which it shall no longer be capable of resisting or protecting
the impurities it may contain from the reaction of acids, as it does when in
.

page_text: compact form or consistence, which resistance or protection has been the chief
obstacle with which the art of refining has heretofore had to contend.
Thirdly, when the gold bullion has been reduced to a pulverulent or spongy
state incapable of resisting the reaction of acids, by treating an alloy of it
with dilute sulphuric acid, all the silver which may have been originally com-
bined with it is still retained by it, as dilute sulphuric acid is incapable of ex-
tracting any portion thereof. To remove the silver, I digest the disintegrated
bullion as in the methods now employed, either in nitric or sulphuric acid with
heat and in any suitable vessel.
Finally, the operations are terminated by melting the refined gold with such
fluxes as borax, nitre, &c., and casting it into ingots or bars. If the operations
have been properly performed, these ingots will be ductile, and of a fincuess
varying from 98-5 to 99.5 per cent., the residual impurity being silver, and
from the solution thereof in nitric or sulphuric acid, the silver extracted from
the gold bullion is then to be recovered by the usual and well known chemical
methods now in use.
For the purpose of explaining the principle which characterizes the present
Invention and discovery, and the several modes in which I have contemplated
its application in the art of refining gold bullion, I will now state first, in
reference to the first operation above described, that it may be varied by melt-
ing the gold bullion to be refined with a sufficient quantity of some other
metal or metals baser than silver, such as iron, copper, &c., to render the
alloy base enough for the action of acid in the second operation. Secondly, that,
in reference to the second operation above described, it may be varied by using
muriatic, nitric, or other acid, instead of dilute sulphuric acid. Thirdly, that,
as the processes, first, of alloying and granulating, and secondly, of treating the
alloyed gold bullion with acids, are intended, as above mentioned, only to
sufficiently disintegrate that bullion, they may be varied in several ways;
thus for example, if the gold bullion be brittle, or if it be rendered brittle by
combining it with small quantities of certain metals, such as lead, or solder,
then it may be reduced to a finely divided pulverulent state, or disintegrated
molecular condition by other means, such as grinding or percussion.
What I particularly claim as new, in the present Invention and discovery,
and desire to secure by Letters Patent as a useful improvement in the art of
refining gold bullion, is,―
First, the reduction of argentiferous and other gold bullion, as a preparatory
process in the art of refining thereof, into a pulverulent or spongy state, or a dis-
integrated molecular condition, by the means particularly of fusion therewith,
and the subsequent removal by acids therefrom, of zinc or other metal baser

page_text: than silver, which will produce the desired effect, for the purpose of theu
separating by means of acids from such gold bullion the silver and other
impurities which it may contain, in order to fit the gold for coinage and other
uses, without quartation with silver or any intermediate process.
Secondly, I also claim, in addition to the above processes, the pulverizing by
grinding, crushing, or percussion of gold bullion, rendered brittle by union
with lead, solder, or other like base metal, for the purpose above set forth.
In witness whereof, I, the said William Edward Newton, have hereunto
set my hand and seal, this Twenty-second day of February, in the year
of our Lord One thousand eight hundred and fifty-one.