The Minneapolis journal., 1903-12-02
WISCONSIN
A NEW ZINC FIELD
Importance Of Southwestern Wis
consin as a Center of the In
dustry Established.
Government and State Cooperate in
a Thoro Study Of the New
District.
Special to The Journal

Madison, Wis, Dec. 2-Director Charles
D. Walcott of the United States geologi-
cal survey is satisfied that southwestern
Wisconsin is likely to have considerable
economic Importance as a center Of the
zinc industry 1t will certainly be news
to many to learn that twenty -one concen-
tration mills have been erected in that dis
trict in the last two years and that seven
teen Of them We're in active operation last
summer.
Deposits Of lead ore have long been
noted In southwestern Wisconsin,, north
ern Illinois, and northeastern Iowa, and
some work has been done toward their
development, but owing to the discovery
of extensive zinc beds below the lead for
nations, the district has recently become
doubly interesting. The ore is not so
clean as that found at Joplin, Mo-, as it
carries a quantity Of iron, and for this
reason it received at first no particular
attention. Improved metallurgical pro-
cesses have. however, shown that this dis
trict contains one of the most considerable
reserve supplies Of zinc in the country.
This fact gives especial significance to
the cooperative studies Of the district that
were made last summer by the United
sin geological and natural history sur
vey. The first organization was repre-
sented by H. Foster Balm and the second
by DR.. y. S. Grant of the Northwestern
University. at Evanston, Ill.
State Survey Work.
The particular feature of the state sur
vey's work was that Of making topo-
graphic and geologic maps on a large
scale. Years ago, before the discovery OF
the underlying zinc beds, the state survey
did some geologic work in the district
with special reference to the lead deposits
The maps resulting from that survey were
RI nn "a 1e Of a 1,a f.ir fn q
mile. The field sheets of those made last
summer were on a scale of eight inches te
a mile, and the printed sheets four inches
to a mile, thus offering increased oppor
tunity for elaborate detail and finish.
Mr. Bains special work was the study
of the ore deposits of the district The
results of his Investigations will probably
be published by the United States Geo
logical Survey in report that will b.
merely part Of more comprehensive worl
on the lead and zinc deposits of the Mis-
sissippi valley.
| "contact Process"
! Three processes for separating the zin
! from the iron ore are in use in south
western Wisconsin. The Mineral Poin
Works Of Mineral Point Wis, which is tn
i property of the New Jersey Zinc company
J. Is one Of the few plants in the countr!
where what is known as the "cOntac
process" of rnanufa cturing sulphuric aci
is employed. sd
This process, which is of German inven
! tion minimizes the cost of the acid an
allows the use of mixed ore. The fume
were formerly confined in lead-line
rooms about twenty cubic feet of spac
| being required for pound of sulphu
burned an hour. BY the new process thes
chambers are discarded and other i'm
provements-trade secrets, however-hav
lately been made. The result is that tn
Mineral Point Works are: able to use
grade of ore than they formerly refused-t
buy.
Other Methods
The roasting process, which is the sec
ond means Of separation In use, is on
that has lately been widely applied !
Colorado. 1t consists of roasting the or
until the iron becomes ma gnetic and the
picking it out with magnets.
The third process. which was likewis
developed in Colorado tho invented j
Kansas, is an application of the principle
of static electricity to the concentration {
ores The direct effect is the opposite {
that produced by the magnets in the roast
ing process. for the electricity repels tn
zinc instead of ragnetizing the iron, bC
the process results. in both cases, in tn
separation of the minerals in the ore. Th
electrical method Is simpler and cheape
The expense of roasting the ore, whic
amounts to about 81 q ton, is saved. j
addition to the zinc blends. an iron su
phide is also obtained. which is sold to tt
!, manufacturers Of sulphuric acid, so thu
!, the process thus affords a valuable BY
! product.
Experiment No Longer.
The zinc industry in southwestern wiz
n consin would seem to have passed the e.
: perimental stage. Some Of the mines hay
paid extremely we'll. The mineralize
area extends into northern Illinois ar
Iowa. In Illinois four or five mines a.
! being developed and a little ore, ha bee
sold. In Iowa all the zinc properties a.
0 still in the development stage.