The Sauk Centre herald., 1903-09-10
slas.rfE PLATINUM,
*Thc ssstot;.,::~,.S as.-..t. .xtr,,etc6 From,
az; T9ils Pc r-.i..r a.-1Stance.

(
sT1ac .tssu,s::s.'' a3>,-..ts. X rs,etcS From,
. SO T{lis Pc E.is.r, ss-i,+ta nee
n On the slopes OF ;'se Ural mountains
and in Drsz:l. Ca. sr:,;a, Australia,
Canada and nl,i!y ctncr countries pc
culiar st:bst&::.cc BROWN rs native pfati-
mum is found. IIis Is an alloy of the
metals platinum, lladiam, iridium,
osmium, rhodiCm and ruthoniun, to-
gether with little gold and iron. All
of these except tie .ast mentioned arc
Thea noble" metals. They DO not tar
nish in the air and arc not soluble in
any single acid The most plentiful
metal occurring ia native platinum is
that from which it takes its name
This metal is OF { grayish cc!or and
with one exception IS the heaviest sub
stance known. It's fusing point is ex-
tremely high, and this property, to-
gether with its freedom from tarnish-
ing. causes it to be largely used for the
manufacture of csTIciJlCs and other
vessels required By scientists to stand
a very high temperature. It 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 lustrons white
color. 1t is the mest easily fused of
the metals found dn platinum 0re. and
can even be volatiIized A curious
quality which this metal possesses is
that when heated to redness It Is
porous to hydrogen gas, allowing it to
pass through somewhat in the same
manner that bIottiag paper Qermits the
:. passage of water The, siRery white
color of palladium and dts freedom
from furnishing render II useful for
making scales and division marks on
scientific Instruments. A mixture OF
this metal with mercury De sometimes
used for filling teeth. Osmium is a
metal which possesses tws remarkable
properties-it ID the most refractory
Of the metals, resisting fusion at the
most intense heat, and Gt is also the
heaviest substance known. being twen-
ty-two and a half times heavier than
water. Together with iridium, 1t oc-
ours principally in peculiar variety OF
native platinum called osmiridfum.
This mineral differs from ordinary
platinum ore in that ut contains
larger proportion of osmium and irid-
ium than platinum. Osmiridium is
found in small particles, varying in
weight from oae-sixth to 'one-third OF
q grain. These particles are extremely
hard and are used for pointing non
wearing pens
Metallic iridium possesses white
steehlike appearance The knife edges
Of delicate balances and other bearings
which require extreme hardness are
.sfte1i made Of it Ah alloy Of 10 per
cent iridium and so per cent platinum
has been found to be very little affected
in volume by changes of temperature
and is the substance of which the
standard meter kept ia the information
al metric bureau at Paris is made.
Rhodium and ruthenium are metals Of
little practical use The former occurs
in pla atinum ore to the extent of to 8
per cent The latter is found only in
osmiridium and averages about. 5 per
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 high atomic weight.
the heaviest known.-Chambers Jour
nal EE- s-.., + - =