The Lee County journal. (Leesburg, Ga.) 1904-19??, 1906-10-19
NATIVE PLATINUM.
rhe "NObIe" Metals Extracted FEOua
This Peculiar Substance.


This Peculiar Substance.
On the slopes Of the Ural mountains
and in Brazil, California, Australia.
Canada and many other countries q pc
culiar substance known as native platf-
mum is found. This is an alloy of the
metals platinum, palladium, iridium,
osmium, rhodium and ruthenium, to-
gether with a little gold and iron. All
Of these except the last mentioned arc
the mobile" metals. They do not tar
nish in the air and are not soluble in
any single acid The most plentiful
metal occurring in native platinum is
that from which it takes It's name.
This metal is Of a gr0yish color and
with one exception Is the heaviest sub
stance known. It's fusing point is ex-
tremely high and this property, to-
gethcr with it's freedom from tarnish-
ing, causes 1t to be largely used for the
manufacture of crucibles and other
vessels required by scientists to stand
a very high temperature. 1t is also
sometimes used as substitute for gold
in photography, and when deposited in
a thin film on the interior Of the tubes
Of telescopes it forms a dead black
surface, which prevents the light from
being reflected by the polished sides.
Palladium is Of a lustrOus white
color 1t is the most easily fused Of
the metals found in platinum ore, and
can even be volatilized. A curious
quality which this metFl possesses is
that when heated TO redness it is
porous to hydrogen gas, allowing 1t to
pass through somewhat in the same
5nanner that blotting paper permits the
passage Of water. The silvery white
color Of palladium and its freedom
from furnishing render it useful for
making scales and division marks on
scientific instruments A mixture CT
this metal with mercury is sometimes
used for filing teeth Osmium is a
metal which possesses two remarkable
propertles-it is the most refractory
Of the metals, resisting fusion ut the
most intense heat. and it is also the
heaviest substance known. being TWEEN
ty-two and a half times heavier than
water. Together with iridium, 1t oc
ours principally in peculiar variety OF
native platinum called osmiridium
This mineral differs from ordinary
platinum ore in that ii contains a
larger proportion Of Osmium and irid
ium than platinum. Osmiridium Is
found in small particles, varying Ia
weight from one-sixth to one-thirS D
a grain. These particles are extremely
hard and are used for pointing non |
wearing pens.
Metallic iridium possesses q white |
steel-llEe appearance, The knife edges
Of delicate balances and other hearings |
which require extreme hardness are |
often made of it. An alloy of 10 p"'
cent iridium and 80 per cent platinur
has been found to be very little affected I
In volume by changes of temperature |
and is the substance Of which the
standard meter kept in the Internal ton !
al metric bureau at Paris is made
Rhodium and ruthenium are metals OF !
little practical use. The former occurs |
In platinum ore to the extent Of to /
per cent The latter is found only IL
osmiridium and averages about . per
cent of that mineral The metal which
ranks next to platinum in price is zir
eonium, which occurs in hyacinth and |
some other rare minerals. Uranium is
remarkable for it's high atomic weight
che hea1 iest known Chambers Jour
Rat