Sapphire
September's Birthstone

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CHEMISTRY Al₂O₃
CRYSTALLOGRAPHY Hexagonal
REFRACTIVE INDEX 1.757 - 1.779
HARDNESS 9
SPECIFIC GRAVITY 3.99 - 4.0
CLEAVAGE None
HEAT SENSITIVE No

WEARABILITY* Excellent
SPECIAL CARE INSTRUCTIONS None

ENHANCEMENTS Heat treated. Common. Diffusion treatment, (places a thin blue coating on colorless sapphire.) Occasional. Irridation, (turns colorless gems yellow, orange or light blue.) Rare.

*Wearability is graded as Excellent, Very Good, Good, Poor, and Forget It!
For more details see the article on "Hardness and Wearability."

... View certified and natural Sapphire gemstones including blue sapphire and pink sapphire.

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