JDMISGem Reference
Corundum · Corundum

Blue Sapphire

Blue Sapphire — Corundum

Blue sapphire is corundum coloured by iron and titanium and the most traded coloured gemstone after, and often alongside, diamond. Kashmir cornflower, Burmese royal and Ceylon blue define its classic origins.

Colour
blue
Transparency
Transparent
RI
1.762–1.770
SG
3.95–4.10
Mohs
9.0
Birthstone
July · September
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