Shepherdstown register. [volume] (Shepherdstown, Va. [W. Va.]) 1849-1955, 1906-08-02
Many New Uses For Mica.

|
isinglass, 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
transparent sheets Of this mineral be-
ing set in the stove door. Through
the "isi 4glass," not destructible when
subjected to heat, as glass would have
been, the glow of the fire within
could be seen.
With long use the mica might be-
come smoked up and opaque, or it
might become marred and broken.
Then the head of the household would
get and set into the stove door fresh
isinglass from the stove dealer, while
the fragments of the old were very
probably turned over to the chill.
dren, 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 a
matter of fact mica, is divisible into
sheets one two.thousandth of an inch
in thickness.
The chief use to which mica is now
put is one not dreamed Of until with
n comparatively few years, name
ly, as an insulating material in the
construction of electrical apparatus,
for which purpose its use is now gen.
eral and constantly increasing, and
far larger than in any use to which 1t
had ever before been put.
Mica is now used also for making
chimneys for incandescent gas lamps
placed where they would be exposed to
drafts, or out of doors, subject to the
weather. Mica is used to make pro-
tectors for ornamental candle shades,
and it is used for making fancy box
es, and, in place of glass, for covering
the labels on drawers, as in desk.
Ground-up mica is now used In the
manufacture of lubricants and of fer
tilIzers, and of dynamite, and in 9TH
er forms it is used for boiler cover
ings.
Mica was long used for windows
and for lanterns, and it is still used
in lanterns where such use would be
advantageous. 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 and still
is put to various other, including or
namental, uses, but among its various
modern uses the chief is in its appli-
cation to electrical machinery. For
this mica is cut into hundreds Of diff
ferent shapes and sizes.
India is the chief source Of the
worlds supply of mica, with Canada
next, the United States third and
Brazil and other countries following.
Mica, from one source and another,
ranges in color from white or trans
parent through various shades to
black.
In the formation in which it exists
it is found in more or lees scattered
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.
One of the chief sources from which
mica can be obtained is the mines Of
Mitchell county, North Carolina. 1t
is found chiefly in small quantities,
although the mining has been very
superficial. Beautiful beryls and
even more valuable stones are not in
frequently found by the mica miners.
The exceedingly rare and valuable
gem, the hiddenite, a fine green stone,
is found only among the mountains Of
North Carolina in the mica country.
The finding of mica In paying guam
titles, together with the unsettled
titles and boundaries Of mountain
land, caused not few murders and
made Mitchell county the most law
less in the State for years.