Improvement in the Method or Process of Treating Gold and Silver Ores, and a Composition of Matter for the same Purpose.
Year: 1894

page_text: Date of Application, 18th June, 1894-Accepted, 21st July, 1894
COMPLETE SPECIFICATION.
Improvement in the Method or Process of Treating Gold and Silver
Ores, and a Composition of Matter for the same Purpose.
I, EDWARD DWIGHT KENDALL, residing at 528 Hancock Street, in the City of
Brooklyn, County of Kings and State of New York, United States of America,
Chemist, 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:-
In treating ores. I usually grind them until a fine division is obtained. I then
prepare two solutions in water, one of sodium di-oxide (Na,O), and the other of a
suitable cyanide. I prefer to use potassium cyanide (KCN), because of its
cheapness. I then unite these two solutions, and mix them with the ore in a
divided condition. Suitable proportions would be sodium di-oxide, four pounds
dissolved in twenty gallons of water: potassium cyanide fourteen pounds dissolved
in eighty gallons of water; divided ore, two tons, more or less, as the character of
the ore may vary; but I do not limit myself to these proportions: the proportions
will vary with the quality of the ore to be treated. I may also accomplish my
process by mixing the sodium di-oxide and potassium or other cyanide and ore
together in a dry condition and adding water thereto. But the constituents of my
composition may be brought together in any required order. I prefer to dissolve
the sodium di-oxide in cold water, and the evanide in a separate portion of water.
cold or hot, mixing the two solutions as required in any desired relative proportion.
Gold and silver ores and tailings may be treated with my composition by lixiviation.
with or without the application of heat, and with or without agitation of the mass
Any suitable receptacle also may be used, as an ordinary leaching tub or rotating
cylinders of wood arranged so that the contents may be discharged into a filtering
tank.
A portion of the pulverized ore may be treated with my composition containing
a relatively small quantity of sodium di-oxide and another portion of the ore may
be treated with the lixivium, after having added to this another small quantity of
sodium di-oxide or a corresponding solution thereof. As many as five such portions
of certain ores may so be successively treated, with intermediate additions of sodium
di-oxide, provided the composition was first provided with a sufficient excess of
cyanide. The small portion of the composition which remains with the ore after
filtration may be washed away with water, and the washings used to prepare fresh
may be
portions of the composition. Gold and silver contained in the lixivium
separated therefrom by electrolysis or other suitable means.
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 treating gold and silver ores, which consists in mixing sodium
di-oxide and a suitable cyanide and water with the ore in a finely divided condition,
substantially as described.
2. The method of treating gold and silver ores, which consists in uniting a
solution of sodium di-oxide and a solution of a suitable evanide, and treating the
finely divided ore therewith, substantially as described.
3. The method or process of treating gold and silver ores, which consists in
uniting a solution of sodium di-oxide and a solution of a suitable cyanide, and
mixing the finely divided ore therewith, then drawing the solution from the ore,
and separating the metal therefrom, substantially as described.

page_text: 4. A composition of matter consisting of sodium di-oxide and a suitable cyanide,
in solution to be used in treating gold and silver ores, substantially as described.
Dated this 18th day of June 1994:
FELL & WILDING,
Agents for the Applicant.