Watertown republican. [volume] (Watertown, Wis.) 1860-1906, 1871-08-02
THE SILVER MINES.
Description of the Smelling Works at
Wynndottc, Michigan.
From the Detroit Free Press

The unexampled richness which has
been developed by the silver mine open
ed last fall on Lake Superior and almost
inexhaustible supply which comes from
that region, which promises to be con-
stantly increased as new mines are
opened, were deemed sufficient reasons
why a silver smelling establishment
should be established somewhere in
the neighborhood, and the same capt.
talists who control the Silver Isletmines
have during the past three months been
engaged in putting up smelling works
at Wyandotte, which are now nearly
ready to go into operation. Indeed,
some of the ore has been already treat
ed, and the superintendent and assist
ants celebrated 4th of July by running
out about three thousand dollars worth
of pure silver, the fist lot obtained.
Although the works are not yet com
pleted SO as to be ready for use in all
departments, yet enough is now done
so that an idea can be obtained of the
various processes through which the ore
has to go before the silver can be ex-
tracted. 1t takes larger number of
operations than most metals before it
union with other metals, and the pro-
cess is a very interesting one.
To begin with the establishment it.
self. The works are located near the
river, and about d quarter of mile be-
low the rolling mills, so familiar to
every one WHO has ever seen Wyandotte
from any point of view. Three stone
buildings, each $50 feet long by so feet
broad, and one story and a half high,
have been erected on the grounds, and
the necessary furnaces and machinery
are beng put in as rapidly as large
force of men can do the work. It may
be proper to state here that, although
silver smelling works have been project
ed in various other places, only one is
IN operation in this country, that at
Newark, New Jersey, and those build
ing at Wyandotte are much more extern
sive, with later improvements The
capacity Of the works, when complet-
ed, viii be about twenty-five tons of
ore q day, and at the rate Of yield that
the ore has given so tar, this viii make
the nice little sum Of $4,000 per day,
or with some Of the richer qualities q
much larger sum.
The first building that visitor
would see contains in one end The
offices of the company, the rooms of the
superintendent and his assistants, a
chemical laboratory, rooms for wet and
dry assaying, and room containing a
variety of scales, used in making the
assays. and IN weighing the pure pro
duct. In the ASSAYS rooms the assist
ants test the richness Of the ores, and
keep the run Of the process, through
all the stages OF the smelling, so as to
7e-e-r- ,iaaa lea@a4aas- af-kh silver Even
the Stag is analysed, and if it contains
Q slight percentage Of the precious ore,
ii is again subjected to the furnace,
that all may be extracted.
Next beyond the Offices is the boiler
and engine-room. A Iow-pressure en-
Gine Of Is horsepower drives the
machinery. In this department is al
50 the blower, which furnishes the
blast for the furnaces. The farther
end Of the building is given up to the
first stages of the operations by which
the ore IS treated to extract It's rich
ness. At the mines the silver-bearino
rock IS assorted acc0r ing to its rich
ness, and classified as No. 2, No. 3,
etc. The better qualities are packed
IN barrels for transportation to the
works, and the poorer ores are sent in
bulk. The first process through which
1t goes is crushing The rock is
shoveled into d pair Of massive iron
jaws, which work together in such a
way as to ''chaw it up into pieces an
inch or less in diameter From that
machine an elevator takes it up and
empties it into hopper, from whence
1t goes to a pair Of millstones, exactly
similar in working to those Of a grist-
mill, but of less diameter. Here it is
ground to a fine powder, and is ready
for the furnace. The other two build
ings are entirly given up to furnaces,
of which there VIII be a large number.
as the different qualities Of ore go
through different processes.
At the river end of the second build
ing will be four reverberatory furnaces,
where the first smelling of the poorer
ore Will be kept in blast night and
day, the ore being drawn off about
once IN twelve hours, in q mat OF what
IS called coarse bullion. In this con-
d1tlon 1t will contain only small per-
centage Of silver.
In the small building, about the
centre, are four cupalo furnaces.
(RrUnaD1 CefeU, with fire-proof compo-
sition bottoms. The second quality
ores, and the products of the reverbera-
tory furnaces are treated here, lead being
added. After being subjected to heat
for about eight hours it is drawn off in
a mat of what is known as silver lead.
1t has next to be followed to the 9th
er building, where it IS once more
melted, there being by this time about
two per cent. of silver in it. Zine is
now melted with /, and it is cast for
the first time into bars. These are
again subjected to heat, sweated, D
and most Of the lead runs out, leaving
what is called zinc dross, which con-
talns about ten per cent. of silver.
The zinc dross is then put into black
lead retorts, and the zinc driven off by
heat. The next operation is carried on
in what are called English cupelling
furnaces, OF which there are two al !
ready in operation. The product OBJ
tanned by the previous operation is |
to an intense heat, which
drives of most Of the remaining i'm |
purites, the lead in the form of liter |
age As the silver comes from these
furnaces it is nearly pure, there being
perhaps slight trace of lead remain |
ing i'm 1t, but it mas still to go through |
one more process before it is ready for
use, in perfectly pure condition. It !
is refined IN graphite crucibles, ana |
when it comes from these it is cast into
bars of bullion, weighing about three
or four pounds, each, and is ready for
market.
But it must not be understood that |
the silver already snelted has gone
through near all Of the operations men
toned. Some Of the richest ore SO far
opSa2ned was put through only the last
Two or three processes, and came out
N ITS purity with much less trouble
thah the poorer ores cause. The result
Of an assay Of ten tons of the first quail
ity gave a. $50 ounces per ton, valued
at %, 1915, yield that has never
been equaled. The average Weld of
the Silver Islet mine is about 81 600