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Precious Metals
By:
www.bidz.com
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PLATINUM |
The platinum group metals (PGM), comprise six closely related metals:
Platinum, Palladium, Rhodium, Ruthenium, Iridium and
Osmium.
Platinum has a deep luster and a rich, white color.
It is rarer, heavier and denser than all precious metals
and considered to be more valuable than gold.
Platinum is often used to set the most valuable gems
to produce the finest jewelry because it holds gemstones
most securely and it neutral color enhances the
brilliance and depth of diamonds and precious stones.
In the United States platinum is usually marked:
PT or PLAT
In Europe, it is marked: 950 or PT950
Platinum Group Metals (PGM):
- Palladium (Pd)
- It is a relatively rare and soft,
silvery white metal. When used in jewelry,
it is alloyed with gold to create white
gold. It is also used to make setting.
- Rhodium (Rh)
- It is a brilliant silvery white metal
that is used as a plating agent on platinum
and white gold to create a white very hard
coating.
- Ruthenium (Ru)
- It is a grayish-white metal that has a
high resistance to wear and is used in the
manufacture of jewelry, porcelain, etc.
- Iridium (Ir)
- It is a white, brittle and extremely
hard metal. The alloy, which contains about
10 percent iridium and 90% platinum, is much
harder than pure platinum. Alloys containing
larger percentages of iridium are used in
making precision and standard instruments,
surgical tools, pen points.
- Osmium (Os)
- It is a bluish-white, brittle metal.
Osmium and platinum alloy is used for
standard weights and measures.
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SILVER |
Silver is the most reflective and affordable of the precious metals.Sterling silver is the standard of quality for
articles containing 92.5% silver and 7.5% copper.
Vermeil is a gold plated sterling silver.
MARKS
- percentage of pure
silver
- General -Sterling Silver
- American - 925
- European - 935
- French - 800
- Russian - 88 or 84
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