Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1904-01-07

/
We quote from the article as
Mining for zine in Wisconsin is
carried on in the counties OF Grant,
Iowa and Lafayette, in the southwest
corner Of the state. Lead appears TO
have been discovered in this district
by Nicholas Perrott about 1892. The
FIRST mining was done on the site OF
the present city OF Dubuque by Julienne
Dubuque, who obtained from the lndi-
ans land on which lead had been dis
covered few years previously. After
Dubuque's death In 1910, little was
done until 1920, and before 1880 min
ing had become quite general in the
vicinity OF Dubuque and Galena, and
also In southwestern Wisconsin; from
that time down to the present day
mining has been carried on continu-
ously with certain periods in which
the district figured prominently as n
producer of lead and zinc. The early
work was devoted entirely TO the min
ing OF lead, the zinc ores being I'M
recognized, or, when recognized, re-
garded as OF little value. 1t was not
until about forty years ago that zinc
ores were mined in this region, and
the production rapidly increased un-
til the district became more important
as Il source of zinc than of lead. The
zine, however, mined in this district
until very recently has been the car
Donate, known locally as "dry bone"
or simply "bonc."
AS the general level OF ground-water
was reached the carbonate was no
longer found, but bende was encount-
ered. AS tho latter locally is associ-
ated with about an equal proportion
OF iron sulphide in the shape of mar
castle, 1t was not salable to the smelt-
ers existing at that time at Mineral
Point. More recently, tho introduce
tion Of magnetic separation has made
this mixture OF iron and zinc sulphides
available.
A Comparison OF the Conditions
in the Wisconsin and Joplin districts
Is OF considerable interest. The adj
vantages in favor of Wisconsin are;
EXTENSIVE DEPOSITS or ORE.-lt
| Is probable that the deposits OF ore in
| Wisconsin are of greater magnitude,
on the average, than those In Joplin.
For example: The Hoskin mine has
n drift 700 feet In length along the
north pitch. The distance from the
north and south pitch Is about 400
feet The vertical thickness between
the top and bottom Hat Is approxi-
mately 100 feet. This would indicate
something over million tons of ore
that may reasonably be expected from
this property. AS to whether the con-
tent OF lack " In this ore will remain
fairly uniform, that Is another matter.
The same chances would necessarily
have to he taken on this point as in
the Joplin mines. AS far as | know,
no Joplin'property has anything like
similar tonnage developed. In those
cases where the brangle" is not suf-
ticiently rich to be put through the
mill, and only the "pitches and
"lats" are worked, the mine is eX-
hausted with great rapidity.
Hen PERCENTAGE OF CoNCEN-
TRATEs. 1t is the usual expectation
in southwestern Wisconsin that the
concentrates produced will amount to
at least 20 per cent of the ore treated,
while in the Joplin district safe esti-
mate is 8 per cent. At first glance
this would indicate that the Wiscon-
sin ores are four times rs rich as the
Joplin ores; and so they are in weight
of concentrates produced; but the av-
erage Joplin concentrate assays Go
per cent metallic zinc, while the aver.
age of the raw concentrates produced