Corundum · Corundum

Ruby

Ruby is red corundum, coloured by chromium, and for centuries the most prized coloured gemstone. Fine stones combine saturated red with red fluorescence that makes the colour glow.

Colour
red

Transparency
Transparent

RI
1.762–1.770

SG
3.95–4.10

Mohs
9.0

Birthstone
July · September

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