Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1906-09-11
Mica Much Used.

There was 4 time when mica. or ISM
glass as it was far more commonly
called, was familiar in one limited use
in every household in which there was
parlor or sitting-room stove, thin,
transparent sheets of this mineral be-
ing set in the stove door. Through the
Using lass" not destructible when sub
jected to heat. as glass would have
been. the glow Of the fire within could
lie seen.
With long use the mica might become
smoked UP and Opaque, or it might be-
come marred and broken. Then the
head of the household would get and
set into the stove door fresh isinglass.
from the stove dealers. while the frag-
ments Of the old We're very probably
turned over TO the children. who were
likely to be surprised to find into how
much thinner sheets still the thin old
pieces from the stove door could be
divided. As matter of fact mica is
Invisible into sheets one tWO-thOu-
sandth of an inch in thickness.
Now there are many who don't know
mica at 2ll, not even as it is used in
stoves. people born and raised in houses
that are heated by steam. in which no
stoves are used for heating purposes;
hut while the number of these is large
and all the time growing. the number
of people who yet use stoves is larger
still; and so while mica my have
passed entirely out of the sight and
monn of many who once knew it in this
use. and in this use only, the prepara-
ton Of it for stove use still constitutes
a regular branch of the mica trade; and
thus one of the old uses of mica still
continues.
The chief use to which mica is now
put is one not dreamed of until within
a comparatively few years. namely as
an insulating material in the ccnstruc-
ton Of electrical apparatus, for which
purpose it's use is now general and con-
stantiy increasing. and far larger than
in any use to which it had ever before
been put
Mica is now used also for making
chimncyS for ircandescent gas lamps
placed where they would be exposed to
drafts. or out of doors, subject to the
weather. Mica is used to make protec-
tors for ornamental candle shades, and
ii is used for making fancy boxes. and,
in place Of glass. for covering the labels
on drawers, as in a desk. Groumd-up
mica is now used in the manufacture OF
lubricants ana of fertilizers, and of dy-
Mantle. and in other forms it is used
for boiler coverings.
Mica was long used for windows and
for lanterns, and it is still used in Ian
terms where such use would be adVan-
tageous. 1t is used in place of glass in
Spectacles worn by stone and metal
workers, and in miners lamps, and it
has been in the past or stili is put to
various other, including ornamental.
uses; but among it's various modern
uses the chief is in its application to
electrical machinery. For this the mica
is cut into hundreds of different shapes
and sizes.
India is the chief source of the
worlds supply of mica, with Canada
next, the United States next. and Bra
iii and other countries following. Mica,
from one source and another ranges in
color from white or transparent.
through various shades to black.
In the formations in which it exists
it is found in more or less scattering
deposits. or in pockets. Its value de-
pends with regard to the uses to which
it may be put. on its color. its freedom
from impurities and the size OF the
sheets that can be obtained from it.
Now this anciently known mineral.
for many years put to varied though
comparatively limited uses, finds more
extensive use than ever in applications