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The Gemstone Fancy Colored Sapphire
Composition: Aluminum Oxide
Class: Oxides and Hydroxides
Crystal System: trigonal; bar 3 2/m
Specific Gravity: 3.99 - 4.0
Refractive Index: 1.757 - 1.779
Luster: vitreous to adamantine
Color: Most any color some stones show zoning
Cleavage: is absent, although there is parting which occurs in three directions
Transparency: Crystals are transparent to translucent
Associated Minerals: calcite, feldspars, garnets, micas and zoisite
Heat treating is Common. Diffusion treatment is done occasionally. Diffusion places a thin blue coating on colorless sapphire. Irradiation is rarely used. Irradiation turns colorless gems yellow, orange or light blue.
Corundum - Ruby and Sapphire:
Ruby and sapphire are actually the same material
called corundum. All colors of corundum other than the light to deep reds and purple-reds are classified as sapphire,
so sapphire can be pink, yellow, green, orange, violet, or colorless in addition to the
commonly known shades of blue. Red and purple-red corundum is classified as ruby.
Corundum is the second hardest natural material, second to diamond,
and because of its durability. It makes an excellent gem for jewelry.
Fancy color sapphires are green, yellow, intense orange to orange-red,
violet to purplish violet, pink, or colorless. With this verity of colors.
Sapphire can be used as durable stones in family jewelry or can accesorise
Sapphire, the traditional birthstone for September, was thought of
as the royal gemstone. It was thought to protect kings from harm and envy.
It was also believed to have medicinal properties.