Grossular

Real mineral · uncommon · Ca₃Al₂(SiO₄)₃

Calcium aluminium garnet occurring in a wide range of colours. The tsavorite and hessonite varieties are the most gem-significant. Forms in metamorphic skarns and marbles where calcium-rich and aluminium-rich rocks interact.

Identity

Formula
Ca₃Al₂(SiO₄)₃
Chemical class
silicate
Mineral group
Demantoid, Garnet, Spessartine, Tsavorite, Uvarovite
Also known as
Hessonite (orange-brown), Tsavorite (green), Leuco garnet (colorless)

Crystallography

Crystal system
cubic
Habits
dodecahedral, massive
Fracture
conchoidal

Physical properties

Mohs hardness
7
Density
3.59 g/cm³
Luster
vitreous, resinous
Colors
orange, yellow, green, colorless, brown, pink
Streak
white
Transparency
transparent, translucent

Geology

Origins
metamorphic
Host rocks
marble, skarn, schist
Associated minerals
Diopside, Wollastonite, Vesuvianite, Calcite
Geography
Canada, Kenya, Tanzania, Russia, Sri Lanka

Classification

Rarity
uncommon
Gem quality
Yes

Arcane properties

Affinity
earth, life
Effects
healing, warding
Planar origin
Material Plane

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