The Lee County journal. (Leesburg, Ga.) 1904-19??, 1907-03-29
NATIVE PLATINUM.
Ehe 'sNObHe' Metals Extracted E'ROm
THIS Peculiar Substance.


This Peculiar Substance.
On the slopes of the Ural mountains
and in Brazil, California, Australia.
Canada and many other countries pc
Guliar substance known as native plati-
mum is found. This is an alloy of the
metals platinum, palladium, iridium,
osmium, rhodium and ruthenium, to-
gether with little gold and iron. All
Of these except the last mentioned are
the noble" 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 1t takes Its name.
TAas metal is Of a grayish color and
with one exception is the heaviest sub
stance known. It's fusing point is ex-
4Fenelv high. and this DroDertv. to-
Refher with its freedom from tarn1sh.
ing. causes it 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 a substitute for gold
in photography, and when deposited in
a thin film on the Interior Of the tubes
of telescopes it ferns 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 metals possesses is
that when heated to redness It IS
porous to hydrogen gas, allowing 1t to
pass through somewhat In the same
manner 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 OK
this metal with mercu9 is sometimes
used for filing teeth Osmium is a
gnetal which possesses two remarkable
properties-it Is the most refractory
Of the metals, resisting fusion at the
most intense heat, and it is also the
aeaviest substance known, being TWEEN
ky-twO and half times heavier than
water. Together with iridium, 1t oc-
ours principally IN a peculiar variety OF
native platinum called osmirid1um'
This mineral differs from ordinary
platinum ore in that IL contains
larger proportion Of Osmium and irid-
INN than platinum. Osmiridium Is
Nsand In small particles, varying In
weight from one-sixth to one-third Of
e grain. These particles are extremely
hard and are used for pointing non
wearing pens.
Natalie iridium possesses a white
ateel-like appearance. The knife edges
OF delicate balances and other bearings
which require extreme hardness are
eften made Of it. An alloy of 10 per
cent Iridium and 90 per cent platinum
has been found to be very little affected
Ga volume by changes Of temperature
and is the substance of which the
standard meter kept in the internation-
nj 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 8 to {
per cent. The latter is found only In
ogmiridium and averages about pei
cent Of that mineral. The metal which
ranks next to platinum in price is zir'
conium, which occurs in hyacinth and
some other rare minerals Uranium Is
remarkable for its hi-h a.'iilr v'"iaht
the hestlpst known -E,ila su5ors' jCu:
GaI