The evening herald. (Klamath Falls, Or.) 1906-1942, 1922-07-14
MICA FOUND To
Be BIG FACTOR
IN Many LINES

l
parlor. or before that new fang.
led" latrobc, watching the glow
OF the CHEEKY winter fire through
the "isinglass" windows' You
may think that since the basement
furnace has generally suppiantcd
the troublesome pesky things the
producers OF 'isingiass" must have
long since gone bankrupt: but
there's more demand for II now
than ever before. says the U. =.
bureau OF mines.
Anyway. Il was not isinglass at
all In the front OF the stove. Had
II been, Il would have lasted as
long as paper, for isinglass IL made
OF the air bladders OF certain fish
and is a soluble combustibie sub
stance. What really was in the
stove windows was mica. one OF
the oldest OF natural substances.
and which is now one OF the great
est boons In the electrical industry
as perfect insuiator. SO i'm
portant Is mica In electrical goods.
It Is declared, that many OF the
larger electrical supply manufac-
turing companies own and oper-
ate their own mica mines.
Mica, says the bureau. includes
a group OF several minerals charac.
terifed by a perfect basal cleavage
by virtue OF which they may be
split into exceedingly thin plates.
How often, as u youngster. did
you make wonderful finds OF
gold" or silver" among the rock
deposits near the homestead! OF
course. the dreams OF wealth van
ished when you found the silvery
or golden flakes were only mica.
Such mica has no commercial value,
IL is only when II occurs In large
deposits where II appears in
books" fairly free from defects,
varying In width and length from
a few inches to fee, and up TO six
inches or more In thickness. Il Is
Of value.
OF the several varieties Of the
mineral only two are OF CONNER
cial value. the "m1scovite" or
white mica, and the "phiosopite"
or amber. India. Canada and the
United States are the chief pro-
ducers.
Mica possesses o combination OF
special qualities which Is found In
no other substance. consequently
no satisfactory substitute has been
found. Chief among these quail
ties are elasticity, toushness, flex-
ibiiity. transparency. ability to
Withstand excessive heat and. sud
den changes OF temperatures q high
dielectsic strength, cleavability and
resistance to decomposition.
An important use OF electrical
mica is for interviewing between
the copper segments Of commute
tors. Thin films are used In vast
numbers In condensers for mag
netos and In wireless apparatus.
As sheets In greatly diversified
shapes. or as washers and tubes.
mica Is used extensively as an in
suiator In dynamos and In various
appliances. In fuse boxes. sockets.
insulators! Electric heaters. flat
irons. telephones. etc.
As a heat-resisting. transparent.
medium, sheet mica Is still used In
furnace slght-holes, for heat
screens. lamp chimneys, canopies
and shades. particularly for gas
mantles. also for military lanterns
and lantern slides.
Its ability to Withstand strains
and shocks. combinel with dts
has led to wide use
In motor goggles, spectcales. divers
helmets. smoke helmets. compass
cards, gage fronts. and In windows
subject TO shock such az on the
coming towers OF battleships.
Owing to the resonance OF mica
circular sheets of high grade mus
c0vite are used extensively In
monographs as sound producing
devices. Such sheets are also used
n other sound detecting devices
'uch as the submarine detectors.
The brilliancy Of its rejecting
Iurface gives the mineral wide
ise as a decoration, notably as
Christmas tree SNOW" Coarse
ground mica Is also used for Or
Of pottery. lamps.
cloth and In India, In
decorating the temples.
An unusual use for the ground
'roduct. whcih. says the bureau OF
mines, fortunately has not ex-
ended outside India" is In medi-
inal preparations and wound
DRESSINGS.
The recent development Of wide
Ises for. the ground product has
Dened N vida field f0r utilization