Improvements in the Treatment of Ores or other Matters con- taining Gold, Silver, or Copper, for the Obtainment of the Metal therefrom."
Year: 1897

page_text: Date of Application, 12th Jan., 1897
Complete Specification Left, 10th Nov., 1897-Accepted, 11th Dec.,
1897
PROVISIONAL SPECIFICATION.
66 Improvements in the Treatment of Ores or other Matters con-
taining Gold, Silver, or Copper, for the Obtainment of the Metal
therefrom."
I, ALEXANDRE ETARD, of 14 Rue Monsieur le Prince, Paris, in the Republic
of France, Doctor in Science, 'do hereby declare the nature of my Invention
to be as follows:-
In treating ores or other matters containing gold silver or copper a solution
of hydrochloric acid in water containing a very small proportion of ordinary
hydrochloric acid per cubic metre (say 30 kilogrammes or thereabouts) does
not noticeably affect the gold or other metal and solutions of permanganate of
potash or of other manganate or permanganate do not affect it much. But I
have discovered that if there be added to such a cold hydrochloric acid solution a
small amount of a manganate or permanganate (say for example about 400 or
500 grammes of permanganate of potash per cubic metre of hydrochloric acid
solution) a liquid is obtained which is devoid of odour of chlorine and is capable
of dissolving gold silver or copper very rapidly and is suitable for the
chlorination of gold silver or copper ore or matter containing such metals
by washing or lixiviation. Care should be taken not to use too highly
concentrated solutions of hydrochloric acid and manganate or' perman-
ganate as then chlorine is produced. But when dilute solutions are used
they form a mixture that is stable during the time needed for performing a series
of methodical filtrations upon the ore or matter to be treated.
If chlorination be properly effected not by chlorine or chlorinated water but by
the simultaneous action of hydrochloric and manganic or permanganic acids the
colour is not liable to change unless metal is (present which turns into a trichloride
free from any odour of chlorine. Ordinary gold-leaf is dissolved in a minute or
two.
The ores
or matters to be treated should not contain any hydrochloric acid
absorbing bases, organic substances, or crude pyrites. Auriferous, argentiferous,
and cuprous, quartz, or earths, calcined if need be and well-roasted pyrites, may
be advantageously treated and yield a very large percentage of the metal contained
therein, say over 90 per cent.
Solutions especially hot sclutions containing a chlorate or a perchlorate and
hydrochloric acid may likewise be used in treating the gold or other ores or
matters.
Such treatment may be effected in filtering troughs or vats sufficiently shallow
to complete the filtration of a charge in 10 or 15 minutes. After having been
filtered the liquid may be passed to another trough or other troughs as long as the
solution remains active. The gold or other metal can be recovered from the

page_text: solution by any suitable agent; such, for example, as sulphate of iron, organic
matter or sulphurous acid."
Dated this 12th day of January 1897
JOHNSONS & WILLCOX
47 Lincolns Inn Fields London W.C., Agents.
66
-
Improvements in the Treatment of Ores or other Matters con-
taining Gold, Silver, or Copper, for the Obtainment of the Metal
therefrom."
I, ALEXANDRE ETARD of 14 Rue Monsieur le Prince, Paris, in the Republic
of France, Doctor in Science, 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 or other matters containing gold, silver, or copper, a solution
of hydrochloric acid in water, containing a very small proportion of ordinary
hydrochloric acid per cubic metre (say 30 kilogrammes, or thereabouts,) does
not noticeably affect the gold, or other metal, and solutions of permanganate of
potash, or of other manganate, or permanganate, do not affect it much. But I
have discovered that if there be added to such a cold hydrochloric acid solution a
small amount of a manganate, or permanganate, of an alkali, or of an alkaline
earth, or a chlorate, or perchlorate, of an alkali, or of an alkaline earth, or an
alkaline chromate, or bichromate, (say for example about 400, or 500, grammes
of permanganate of potash, or of the other alkaline compound selected.) per cubic
metre of a two, or three, per cent. hydrochloric acid solution, a liquid is obtained
which is devoid of odour of chlorine, and is capable of dissolving gold, silver, or
copper, very rapidly, and is suitable for the chlorination of gold, silver, or
copper, ore, or matter containing such metals by washing, or lixiviation, Care
should be taken not to use too highly concentrated solutions of hydrochloric acid,
and manganate, or permanganate, or other alkaline compound, used, as then
chlorine is produced. When dilute solutions are used they form a mixture that is
stable during the time needed for performing a series of methodical filtrations upon
the ore, or matter to be treated. If chlorination be properly effected, not by
chlorine, or chlorinated water, but by the simultaneous action of hydrochloric
acid and an alkaline compound as aforesaid, the colour is not liable to change
unless metal is present which is converted into a trichloride free from any odour
of chlorine Ordinary gold leaf is dissolved in a minute, or two.
The ores, or matters, to be treated, should not contain any hydrochloric acid
absorbing bases, organic substances, or crude pyrites. Auriferous, argentiferous,
and cuprous quartz, or earths, calcined if need be, and well roasted pyrites, may
be advantageously treated according to this invention and yield a very large per-
centage of the metal contained therein; say over 90 per cent.
When solutions of a chlorate, or a perchlorate, with hydrochloric acid are used
the said solutions may be hot, or cold.
The treatment may be effected in filtering troughs, or vats, sufficiently shallow
to complete the filtration of a charge in 10, or 15, minutes. After having been
filtered the liquid may be passed to another trough, or other troughs, as long as
the solution remains active.. The gold, or other metal, can be recovered from the
solution by any suitable agent; such, for example, as sulphate of iron, organic
-matter, or sulphurous acid.

page_text: Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I
claim is:-
1. The treatment of ores, or other matters, containing gold, silver, or copper, by
means of a cold and weak solution of hydrochloric acid, in conjunction with a small
amount of a manganate, or permanganate, of an alkali, or of an alkaline earth.
2. The treatment of ores, or other matters, containing gold, silver, or copper, by
means of a weak solution of hydrochloric acid, in conjunction with a chlorate,
or a perchlorate.
3. The treatment of ores (or other matters containing gold, silver, or copper,
by means of a weak solution of hydrochloric acid, in conjunction with a chromate,
or a bi-chromate.
1000
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.