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Sapphire: The Jewel of the Sky
Sapphire has been sought after for thousands of years
as the ultimate blue gemstone. The ancient Persians
believed that the earth rested on a giant sapphire that
gave its blue reflection to the sky, hence the Latin
name "sapphiru", which means blue.
The gem has long symbolized faith, remembrance, and
enduring commitment. According to tradition, God gave
Moses the Ten Commandments on tablets of sapphire, making
it the most sacred stone. This supposed "divine
favor" is why sapphires often were the gem of choice
for kings and high priests throughout history. In fact,
the British Crown Jewels contain a number of notable
sapphires. Prince Charles even gave Princess Diana a
sapphire engagement ring.
Sapphire is the birthstone for September. It is also
the recommended gem for couples celebrating their fifth
and 45th wedding anniversaries.
Both sapphire and its sister stone, ruby, are part
of the corundum family, one of the strongest minerals
on earth. The stone is mined in many parts of the world,
including Australia, Cambodia, China, Kashmir, Kenya,
Madagascar, Myanmar, Nigeria, Sri Lanka, Tanzania, Thailand,
the United States and Vietnam. Sapphires from Kashmir
and Myanmar are rarest and most prized because of their
vivid blue, velvety look.
Although sapphire is virtually synonymous with blue,
the stone also comes in a variety of fancy colors that
includes colorless/white, pink, yellow, peach, orange,
brown, violet, purple, green and many shades in between
(except red, because a red sapphire would be called
a ruby). Some sapphires that are cut into a cabochon
(dome) shape even display a six-rayed white star. These
are called star sapphires, and the ancients regarded
them as powerful talismans that protected travelers.
Like other gemstones, color is the main determining
factor when judging the value of a sapphire. As a rule,
the most valuable sapphires have a medium intense, pure
vivid blue color and hold the brightness of their color
under any type of lighting. Any color undertones - usually
black, gray or green - will reduce a stone's value.
Although a pastel stone would be less valued than a
deeper blue one, it would be more valuable than a stone
considered too dark. In selecting your sapphire, keep
in mind that the finest stones are "eye clean",
with little or no inclusions (flaws) visible to the
naked eye.
Sapphire is readily available in sizes of up to 2 carats,
but gems of 5-10 carats are not unusual. The stone is
most often cut in a cushion shape - a rounded rectangle
- or an oval. But smaller stones are available in round
brilliant cuts and a variety of fancy shapes, such as
triangle, square, emerald, marquise, pear, baguette,
cabochon and others.
Some of the more noted sapphires include the Logan
Sapphire, a 423-carat cushion-cut stone from Sri Lanka
currently in the Smithsonian Institution in Washington,
D.C., and a 258-carat stone set in the Russian crown
and kept in the Diamond Fund in Moscow.
With a hardness of 9 on the Mohs scale, sapphire is
harder than any other gemstone except a diamond. This
quality makes it extremely durable for everyday jewelry
pieces subject to repeated impact, such as rings and
bracelets. In general, sapphire can be cleaned with
soapy water or commercial solvent and a brush.
It is estimated that about 90% of sapphires on the
market today have been heated to maximize their color
and clarity. This process is permanent and completely
stable. Perfect natural, untreated gems are exceptionally
rare and very expensive. Some colorless or pale stones
are treated with chemicals (diffusion treated), which
improves the surface color only. This could create a
problem if the stone is ever chipped or nicked and needs
to be recut or repolished. In addition, some fancy colored
sapphire is irradiated to give it a more intense shade.
These effects are temporary and can fade in light or
heat.
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