The Superior times. [volume] (Superior, Wis.) 1870-1912, 1904-04-30
NATIVE PLATINUM.
The ~Hobie" details Extracted From
rhis Peculiar substance.


on the slopes of the ural mountains
and In Brazil California, Australia,
Canada and many other countries II pc
cuiar substance known ~ native plnti.
aum IL found This IL an alloy Of the
metals platinum, palladium, iridium,
osnium, rhodium and rulhcnluu, to.
gcther with lltlr gold and iron. All
OF those except the last mentioned are
the mobile" metals They do not tar
nlsh In the air and are not soluble In
any single acid The most plentiful
metal occurring In native platinum Is
thnt from which II takes ls name.
This metal Is OF grayish color and
with one exception Is the heaviest sub
stance known lts fusing point IL ex
trcmely high, and this property, 10
gcthrr with It's freedom from tarnish
fng, causes II TO be largely used for the
manufacture of cruciblCs and other
vessels required by scientists to stand
very high temperature II is also
sometimes used as n substitute for gON
In photography, and when deposited in
thin nlm on the Interior OF the tubes
Of telescopes II forms dead black
surface, which prevents the light from
being reflected 10y the polished sides.
Palladium IL OF lustrous white
color II IL the most easily fused of
the metals found IN platinum ore, and
can even he volatilized A curious
quality which this metal possesses IL
that when heated TO redncss II IS
porous 10 hydrogen gus, allowing II to
pass through somewhat In the same
manner that blotung paper permits the
passage OF water The silvery white
from furnishing render II useful for
making scales and division marks oi
scientific instruments A mixture ot
this metal with mercury IL sometimes
used for filling teeth ONnium Is II
metal which possesses two remarkable
properties 1t Is the most refractory
OF the metals, resisting fusion nj the
most intense heat, ana II IL also the
heaviest substance known, being TWEEN.
ty-two and half times heavier than
water Together with Iridium, II oC
ours principally In a peculiar variety OF
native platinum called osmirdlum
This mineral differs from ordinary
platinum ore In that IL contains u
larger proportion of osmium and irid
ium than platinum Osmlrtdium Ia
found tn small particles, varying In
weight from onC.siNth 10 unc-third nf
q grain These Particles are cNtrrWcly
hard and ARE used for pointing uou
wearing pens
Metallic iridium possesses a white
steel-llkc appearance. Ihe knlrr edges
OF delicate balances and other bearings
which require eNtrrl1e hardness arr
often made Of II. An alloy ~ 10 p
cent iridium aud ~ per cent platinum
has been found TO be very little affected
In volume 10y changes OF trmpcratut
and Is the substance ~ which the
standard meter kept in the tnternatioe
al metric bureau AT Paris Is made
Rhodtum ana ruthenium orv metals o.
little practical use. The former oecun
In platinum ore 70 the extent or = 10
per cent The latter Is found ouly IL
osn,iridium aud averages about . pc
cent of that mineral The metal whici
ranks next 10 platinum IN price Is UT
eouium. which occurs IN hyacinth aud
some other rare minerals Uranium l
remarkable for its hiE, atomic ~etsh'
the heaviest known. -Chanters Jour
ual