18K White Gold Real Gemstone Diamond Necklace Natural Sapphire
Metal Type: Solid 18Kt Gold-White
Sapphire:Genuine 100% Natural
Approximate Weight: 1.73-1.80g
Sapphire Weight: 0.485-0.58ct
Necklace Length:16-18 Inch
Sapphire is the official birthstone for the month of September as
adopted by the American National Association of Jewelers in 1912.
It is also one of the birth stones for the Zodiac signs of Pisces,
Taurus, Virgo and Sagittarius. See the birthstone tables for
additional references to this stone. Sapphire is given as a gem for
the 5th, 23rd and 45th wedding anniversaries while a star sapphire
is given on the 65th wedding anniversary.
Sapphire is the non-red variety of corundum (the red variety of
corundum is ruby). A 9.0 on the Mohs scale of hardness, sapphire is
the second hardest natural mineral.
Blue is by far the most popular color for sapphires, but they can
be almost any color, including yellow, green, white, colorless,
pink, orange, brown, and purple. Padparadscha is the name for a
rare orange-pink variety of sapphire and has a higher value than
Sapphires with inclusions of tiny, rutile needles exhibit an
optical property called asterism. This is the star shaped effect
seen in star sapphires and is usually only seen in cabochon cuts.
Star sapphires usually have six ray stars, but twelve ray stars are
also known. Rarely, when sapphires are cut en cabochon, they can
demonstrate a cat's eye effect. This effect displays a thin band of
light down the center of the stone and is known as chatoyancy.
Heating colorless and very pale blue sapphires to high temperatures
is done to give them an intense blue color This treatment can also
improve the clarity of the stones by removing tiny inclusions.
A rare variety of sapphire, known as color changing sapphire,
exhibits different colors in different light. A color change
sapphire is blue in natural light, and violet in artificial light.
A similar effect is also seen in alexandrite.
Sapphire was first created synthetically in 1902 and is hard to
distinguish from natural sapphires except by gemologists. Lab grown
sapphires range in price and smaller stones are frequently used in
less expensive jewelry.