The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1923-02-22

been IN use IN Europe Tor about luu
years, and some of the original roofs
are still in place and i'm good condi-
ton A few zinc roofs We're put on by
the Old Lehgh Zinc company when it
operated rolling mill i'm Bethlehem
some time between 1860 and 1870. The
roofs We're in perfect condition when
the buildings were torn down after so
years and had never required repairs
and were never painted.
For flashing cutters and leaders
zinc is an ideal material it suitabl,
grade of zinc is used and is properly
installed. There are several grades OF
zinc ON the market containing vary
ing amounts of impurities For most
of the purposes for which zinc is used
these impurities are not injurious i'm
the quantities in which they occur i'm
commercial zinc, but they all make
the zinc harder and more brittle es-
Ipecially at low temperatures As the
sheets used for flashing cutters and
leaders must be bent sharply. and Of
ten in cold weather. only the pwest
zinc should be used for these purposes.
Use Of Zinc Castings
Zinc castings are used to an extent
that very few realize, as they are
nearly always plated with some other
metal and usually are sold to the
consumer as bronze All sorts of or
namental objects as bronze. electric
fittings, lamps, jardinieres. ash receiv-
ers, ink stands, etc. are made in this
way Zinc is very suitable for such
purposes, as it makes sharp and ac-
curate castings which can be plated
with any metal.
Zinc is also used in separating sill
yer from bullion. In great many
cases silver and lead occur in the /
same ores. and when these ores arc |
smelted the resulting metal, or bul
lion, contains both the lead and the
silver-a ton of bullion containing on
ly about 100 to 200 ounces of silver [
The easiest way to separate them Is
to add some zinc to the melted bullion
at temperature high enough to melt h
the zinc. The mixture is then cooled
slightly. when the zinc and silver
freeze together and can be skinned
out. The result is that the silver is
recovered in combination with a very
small amount of zinc. from which il |,
can be easily separated by dstillation.
Still another form in which zinc is
produced is a fine powder. called zinc
dust, largely used in dyeing and i'm
the manufacture of dyes, in recovering
the gold extracted from ores by the
cyanide process, in flashlight powders
and in other products. During the
war great deal was used in shells to
give cloud Of white smoke to mark
where the shell struck.
Zinc Used in Paints.
In addition to its use as a metal, a
great deal of zinc is used in making
salts and pigments The most largely
used salt of zinc is the chloride, which
is used in preserving timber from rot
ting and in making fiber ware
The two zinc pigments are the OK
ides, either commercially pure oxide
Of zinc or mixtures Of zinc oxide and
basic sulphate of lead Olnown as
Headed oxide'). and lthopone, a mix
ture of sulphide of zinc and suphate
Of barium.
Zinc oxide is one of the most largely
used pigments and is used i'm all of the
better enamel paints, flat wall finishes
and most of the mixed paints 1t is Of
pure and brilliant white and does not d
iarken or change color on exposure
nor does it chalk or rub off Expert 9
oil, f.-tt . Z
nents gives a better paint than any II
single pigment Zinc oxide on account
If its good and uniform color and per
nanence is the most valuable single "
OF these mixed paints. IT
s also used in the manufacture of j.
,nameled cloth, oil cloths and linole-
ms.
The loaded oxide is not of quite so
good color as the pure zinc oxide, !
mt is an excellent pigment and is
argely used in tinted paints
A very pure variety known as phar-
oxide is made by special
from selected materials and
s used in medicine, for face powders
md other purposes where extreme
purity is necessary During the war
he name of Sag paste" as a protec-
ion from from and cure for mustard L
yas burns.
Zinc in Automobile Tires.
Zinc oxide is very largely used in
he manufacture Of rubber goods Pure =
ubber alone is useless for such me-
'hanical purposes as automobile tires
\ tire of pure rubber would wear out u
n less than 100 miles but when rein
orced by a pigment such as zinc OK
de, this can be increased to 5000 or
TO- 900 miles. Few people realize t. p
IN automobile tire may contain as
much as 25 per cent Of its weight in a
zinc oxide
Zinc oxide has been used success
uily as a rubber filler ever since the O
development of rubber compromising
rIfc ic dino n,.inoina11v tO fhp fact that r