Sapphire

Real mineral · very rare · Al₂O₃

Corundum coloured blue by iron and titanium impurities. The same mineral species as ruby, distinguished only by colour. Formed in metamorphic and igneous environments, often recovered from alluvial deposits.

Identity

Formula
Al₂O₃
Chemical class
oxide
Mineral group
Corundum, Ruby
Also known as
Blue corundum

Crystallography

Crystal system
trigonal
Habits
tabular, prismatic, pyramidal
Fracture
conchoidal

Physical properties

Mohs hardness
9
Density
4 g/cm³
Luster
vitreous, adamantine
Colors
blue, sky blue, dark blue, yellow, pink, colorless, orange
Streak
white
Transparency
transparent, translucent

Geology

Origins
metamorphic, igneous
Host rocks
marble, basalt, gneiss
Associated minerals
Ruby, Spinel, Tourmaline, Zircon
Geography
Sri Lanka, Myanmar, Madagascar, Australia, Kashmir

Classification

Rarity
very rare
Gem quality
Yes

Arcane properties

Affinity
water, air
Effects
scrying, mind
Planar origin
Material Plane

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