The Western news. [volume] (Libby, Mont.) 1933-current, 1941-04-24
Strategic Minerals
of Montana
VERMICULITE
BY Carl ]. Trauerman

NO1E llllS Is THE SeCOllQ Vi ser
les of popular articles on strategic
minerals in Montana. These ar
ticles are being prepared by Mon
tana Mineral Resources Survey, a
cooperative enterprise conducted
jointly by Montana School of Mines
and the Works Projects Administra-
ton of Montana. Other articles
will follow shortly.
Do you believe in magic? Of
course you don't and neither do we
but there are certain things that go
on in nature that closely approach
the arts practiced by the magicians
that you have seen on the stage.
For instance, nature has taken
hydrogen and magnesium, both of
which are, by themselves as ele-
ments, highly inflammable and has
chemically combined these in the
proper proportions with potash,
aluminium. and silica. The COM
bination is kiown as phlogopite
mica, or more specifically, as jeffer-
isite or vermiculite, greenish-
black mineral. If we heat this min
eral, we carry our magic one step
further as it seems to come to life,
wriggles like worm, turns gold
en- color, and becomes very light in
weight. In fact, given amount
of the heated material will occupy
about six times the space of the raw
mineral and in spite of the fact
that it contains some highly in
flammable elements, vermiculite is
fireproof. 1t is said that the Chi
nese used vermiculite in the manu-
facture of fireworks, especially the
pyrotechnic which we knew in
childhood as snake in the grass. :"
The mineral derives its name from
the Latin word "vermiculari" which
means to breed worms.
Vermiculite is practically new
mineral and it is stated that it was
not used commercially before 1924
when only two tons were produced
in the United States. While it is
not primarily strategic mineral, a
great many uses are being found
for it in the present national de-
tense program. 1t is being mined
in Montana, North Carolina, Colo
RADIO, Wyoming, and Pennsylvania;
and in 1887 over $4,000 tons were
produced. 1t is believed that much
larger tonnage than this will be
used during the current year and
that large part of it will come
from Montana.
In the northwestern corners of
Montana on Rainy Creek, about 8
miles northeast of Libby, Lincoln
County, there is large deposit of
this material on what is known as
Vermiculite Mountain. This deposit
is controlled by the Universal Zon-
olite Insulation Company OF Chi
cago. which is consolidation of
three former companies and OF
which A. T. Kearney is president.
1t is reported that the Armour pack
ing interests of Chicago are finan-
cially interested in the company
This company sells its product un-
der the trade name of "ZOnolite. :"
In order to mine this material, a
heavy monumental overburden is
removed by bulldozers, Fresno
scrapers, and picks and shovels. AT
ter this operation combined ro-
tary screen and loader is backed in
to the face of the ore. The screen
removes all waste over one-half
inch in diameter. The cleaned YER
miculite, that passes through the
screen, is conveyed by an elevator
to truck which transports it to
the milling plant The plant sorts it
into the different sizes needed for
the trade and when the vermiculite
is shipped raw it is packed in 100
pound sacks. The company also
heats the ore and expands it and
the expanded product is shipped in
25-pound sacks. The raw material
usually sells at from $500 to $1,000
per ton, t. O. b. the mine, and the
heated, or exfoliated, product sells
at from 80 cents to $1,35 per Is
pound bag, f. 0. b. the plant
The expanded product is used to
make wallboard and outside build
ing board and cement, as the ma
terial is waterproof 1t also is used
as an insulator and mixed with 9TH
er materials to make roofing. One
of the manufacturers stated that
three inches of expanded vermicu-
lite, used as a house insulator, will
give an insulating value equal to
q J-lDOl DliGh wall VI q t-1OOk COll-
crete wall 1t also is used as an
insulator in refrigerating equip
ment and in open-hearth furnaces of
the steel mills. When used for
roofing, it is said that an attic room
is cool even in the summer.
Vermiculite is used in nearly all
the talking movie studios as it is
sound proof and makes a room
"echoless." Due to this quality, it
is now being tested in airplane con-
struction, both for commercial and
military planes, as it deadens the
sound of the motors.
Recently the expanded product
has been ground through 325 mesh
and the powder is used as an ex-
tender for aluminium paints, thus
increasing the paint coverage by Is
per cent. The powder is also used
as coolant and lubricating agent in
commercial and military trucks,
tanks, and cars to lubricate the mo-
tors, transmissions, and rear ends.
1t is believed that a great many
other uses will be found for ex-
banded vermiculite and that ex-
panding plants will be placed close
to the points at which the products
will be used as it is cheaper to ship
the rauy yprpir,,1ifo than II ic IN