Eureka daily sentinel. [volume] (Eureka, Nev.) 1871-1887, 1878-06-20
fEsTIsG SILVER oars.
Practical Hints to Miners and Pro
pecfOrs.

PrHcf1c0I Ihhmhs 70 hnek3 Anu fEos-
pect0rss
Mr.. Charles H. Aaron has written o
valuable little work on testing and treating
silver ores, and tho treatise ought to be in
the hands of every miner and prospector
in the country. As showing its scope we
extract the following practical suggestions.
The information is really valuable. He says:
In the mineral districts OF Mexico nearly
every miner has some knowledge, however
rude, Of metallurgical operations, which
enables him TO work in one way or another
any small rich hilo which he may discover,
and though in large operations the Mexi-
can may not be able to compete with more
enterprising people, yet it is a fact that
among miners and prospectors a Mexican
will make a good living where an American
would starve to death. He maintains that
If his modification Of the old london Of
Alonzo Barba had been adopted for the
Comstock mines long ago, many millions
Of dollars which are now in the Carson
river might be in the pockets Of stockhold-
ers, and the value OF stocks would be
proportionately higher. The whole Of his
directions are concise and clear. The
prospector, having found a sample that
looks promising, is directed to grind a few
ounces Of the ore 10 powder between two
rocks, add to it about one-tenth as much
salt, and about half that quantity Of sui
pbate OF iron, which Is often called cop
peras, then mix them all together, and
after that is lone put it into an old shovel
or frying pan, which should have been pre-
v~iously smeared with clay or mud, and
dried, then roast it over q fire. being care
full to stir ii often with a piece of stout iron
wire. Let the roasting proceed quite
gently a. long as the smell OF burning sui
phur can be perceived, not allowing the
heat to exceed a dark red, as seen at
night. When the fumes Of sulphur
cease let the heat increase to a rather
light red. but not 80 az TO melt the ore.
stirring it with the wire. The smell will
now be thai Of chlorides, rather pungent,
often sweet, as Of new hay, but very easily
distinguished from that Of sulphur. The
ore will swell and appear woollt, and
somewhat sticky, and a few minutes Of this
latter roasting will finish it well enough
for your purpose. Now, transfer the roast
ed ore to a flat rock and let ii cool add q
little more salt, and enough water to make
II like mortar imbed In the mass o strip
Of clean sheet copper, and let it remain
ten minutes take the copper out, and
without touching the part that has been in
the pulp wash the mud of it with clean
water. II the ore contains silver it will in
variably show as a white coating on the
copper, and ~ no other metal will so coat
the copper under these conditions, the APP
pearance Of such a coating is proof positive
OF the presence Of silver. The white coat
ing will be heavier or lighter according to
the richness Of the ore il very heavy ii
will appear grey and rough.
Mr.. Aaron naturally seeks to reduce his
testing apparatus to the simplest form, and
hence he only proposes to employ for the
tests just mentioned, salt, sulphate Of iron.
an old shovel or ~frying-pan. q piece Of
stout iron wire. and a strip of sheet cop
per 6 inches long ; whilst for another test
he only requires salt, bluestone, q strip of
copper. and a teacup or a basin, which can
be set in the top Of an empty oyster can.
He has never found these tests fail TO de-
termine whether the ore is valuable or
otherwise. The next step is Of course to
determine what process will be most adj
v~antageous 10 treat it by, for, as Mr.. Aaron
remarks, although very rich ore will bear
transportation to a market, yet the losses,
expenses. and discounts which are INSOFAR |
able from this way OF disposing Of il have
caused miners in general to entertain a
strong and not unfounded objection to sell
ing their ores, especially when the market
is very distant and he explains that
whether the mill is 10 be large or small il
is equally necessary TO find out before
building II whether the ore can be worked
raw or must be roasted or smelted. Mr..
Aaron next describes his process
for working ores, and he remarks that
his first operation was conducted
on about a grain Of ore in a minute por-
celain cup. with the aid OF a copper belt
rivet, the next was on 5 pounds Of ore in a
kettle, then on l ton in Il wooden barrel,
and subsequently thousands of tons have |
been worked by ii, and near ST ,000, 900 ex-
tracted. The method Of working roasted
ores, the teaching processes, and smelling,
are then referred to. and he observes that
when a Mexican finds rich ore, and can
get galena in the vicinity, he puts a little
furnace of adobes, smelts out his silver
lead, refines 1t in another furnace, and
buys beans with the proceeds. Why, asks
Mr.. Aaron, can not intelligent Americans,
who have opportunities Of seeing smelling
carried on, go and do likewise? In course
of time the knowledge would spread, and
many honest miners might profit by their
discoveries, instead Of waiting for capital.
or abandoning their mines because they
can not sell them.