| Platinum
In most countries, diamonds are usually mounted in gold. Japan,
however, is an exception. It's estimated that over 90% of
all wedding and engagement rings sold in Japan are of platinum.
[n fact, 75% of all platinum jewelry in the world is bought
by the Japanese. To understand why this metal is so prized
in Japan, it's helpful to examine some of its characteristics.
Platinum
Characteristics
Does
not corrode, tarnish, or rust.
Can be easily flattened and worked in its pure state, but
not as easily as gold. It becomes much harder to work with
when mixed with the metal, iridium, its most common alloy
in jewelry.
9 Has a melting point of 1773° C. (3224° F.), about
1.65 times higher than that of gold.
harder
than gold and silver, so it outwears them and is not as easily
scratched. It's hardness is 4 to 4.5 on Mohs' scale of hardness,
about the same as iron. When platinum is with iridium, it
becomes much harder and therefore more suitable for jewelry
wear. a grayish-white or steel color. It shines well but is
not as reflective as gold or silver.
Is
very heavy compared to other metals. It's 21.45 times heavier
than water, about twice as heavy as silver, about 1.65 times
heavier than 14 karat gold, and about 1.4 times heavier than
18 karat gold. Mixing platinum with 10% iridium makes it only
slightly heavier.
Is
very rare and expensive, even more so than gold. The major
sources are South Africa, Canada, the U.S.S.R, and Colombia.
(For a short time in 1991, however, the pric¬e
. platinum did fall below that of gold. This occurred only
two other times during the previous 15 years).
Harder
and therefore
Hardest
metal known
Probably
be better
Chapter
Nine since
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