
Gold
Pure gold is a very soft and pliable metal. The extreme malleability,
ductility, and softness of pure gold makes it practically useless for
jewelry applications. Jewelry made of pure gold would easily bend and
distort in the course of normal wear. To get around this problem,
jewelers use an alloyed form known as karat gold (not to be mistaken
with metric carat used to measure diamond weight). Alloying increases
gold's hardness and provides a variety of different colors. White gold
contains about 10 - 20 % nickel, plus zinc, copper, platinum, and
palladium. These alloys make white gold a harder metal than yellow gold.
Gold content is specified by the codes 14K, 18K, etc. The K (karat)
number specifies how many parts, by weight, of pure gold is contained in
24 parts of the alloy. Thus:
10K = 10/24 = 41.67% pure gold 14K = 14/24 = 58.33% pure gold
18K = 18/24 = 75.00% pure gold
And of course, 24k means 100% pure (or fine)
gold. Gold itself is impervious to tarnishing and requires very strong
and dangerous chemicals for it to dissolve. Gold in jewelry making is
not always gold in color. There are many colors such as white, pink,
green, red as well as various shades of yellow.
Platinum
Platinum is regarded as the preeminent metal for fine jewelry. It is
rarer and thus more expensive than gold. The white luster of platinum is
unique. It is also the strongest precious metal used in jewelry, and is
almost twice as heavy as 14k gold. This weight is one of platinum's
strongest selling points, because it gives "heft" to fine jewelry, which
people naturally equate with value. Platinum has rapidly grown in
popularity in recent years, becoming the new choice for many diamond
engagement rings because the luster of platinum is said to bring out the
brilliance of diamonds better than gold. Platinum in jewelry is actually
an alloyed group of six heavy metals, including platinum, palladium,
rhodium, ruthenium, iridium and osmium. These other metals are so
similar to platinum in weight and chemistry that most were not even
distinguished from each other until early in the nineteenth century.
Today it is often alloyed with copper and titanium. It is the only
precious metal used in fine jewelry that is 90% to 95% pure, largely
hypoallergenic and tarnish-resistant. Platinum jewelry is marked 900Pt,
950 Plat, or Plat.
Gold and platinum are durable, sturdy and
dependable, and make ideal settings for your precious diamond jewelry.
However, to get a lifetime of enjoyment from your jewelry, be sure to
keep it clean and safe.
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