Precious Metals

Platinum

Platinum is among the finest, purest, and rarest precious metals. One of the strongest and
most enduring of metals, it is also one of the heaviest. A piece of jewelry containing 90 percent
pure platinum weighs 60 percent more than a 14 karat gold piece of similar size.

Platinum is ideal for jewellery that's worn everyday because it shows little wear. It's also hypo-
allergenic and resists tarnish. Platinum jewellery is pure. In the United States platinum jewellery
generally contains anywhere from 85 to 95 percent pure platinum. By comparison, 18 karat gold
is 75 percent pure gold and 14 karat gold is only 58 percent pure gold. If a piece of platinum
jewellery is marked "Platinum" then it contains at least 95 percent pure platinum. Jewellery with
85 to 95 percent pure platinum is marked "950 Plat." or "950 Pt.," "850 Plat." or "850 Pt.," etc.
Both the two-and four letter abbreviation for platinum is used.

Jewellery containing at least 50 percent pure platinum and at least 95 percent platinum group
metals (platinum, palladium, iridium, osmium, rhodium, and ruthenium) is marked with the platinum
content followed by the content of the other metal. For example: "600 Plat. 350 Irid." or "600Pt 350Ir"
Jewellery containing less than 50 percent pure platinum content cannot be marked with the word
"platinum" or any abbreviation thereof.

Platinum is rare. To produce a single ounce of finished platinum, a total of 10 tons of ore must be
mined. In comparison, only three tons of ore are required to produce one ounce of gold. This rarity
gives platinum its cachet.

Signs of wear, including scratches, will inevitably appear in all precious metals, even in platinum.
However, due to platinum's durability and strength there is usually little metal loss when the piece
is scratched. If your platinum jewellery does develop visible scratches, you should have the piece
repolished by a professional goldsmith.

PLATINUM...
is obtained as a by-product, along with gold and silver, in the refining of nickel and copper. It was once used
for coinage in Russia.

Platinum is grayish white,
very ductile and malleable.
Its melting point is very high - 3224'F.

10% of iridium is added to
platinum in order to increase
its hardness.

Platinum is a heavy metal (S.G.= 21.5), about 1.6 times heavier than 14K gold.

Platinum/Gold/Silver melting point comparison:

Purity of metal	Colour of metal	Name	Melting Point
90%	white	Platinum	3224'F
24K	yellow	Fine Gold	1945'F
18K	white	Gold	1730'F
18K	yellow	Gold	1700'F
14K	white	Gold	1825'F
14K	yellow	Gold	1615'F
10K	yellow	Gold	1665'F
99.9%	white	Fine Silver	1762'F
92.5%	white	Sterling Silver	1640'F
90.0%	white	Coin Silver	1615'F

The Platinum Group:

platinum, palladium, iridium, osmium, rhodium, and ruthenium

Care & Cleaning of Platinum:

When storing platinum jewellery for safekeeping, separate the items to prevent any chance of scratching.

To clean jewellery use a cleaning solution, or ultrasonic machine. Avoid soap and soapy water since it can create a film. Dry and polish with a soft cloth.