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cubiccommonsilicates
Garnet
X3Y2(SiO4)3 (where X = Ca, Mg, Fe2+, Mn2+; Y = Al, Fe3+, Cr3+)
Garnet is a group of silicate minerals typically forming well-developed dodecahedral or trapezohedral crystals, often deep red but occurring in a wide range of colors.
Garnet Physical Properties
Mohs Hardness
7Crystal System
cubicLuster
vitreousStreak Color
whiteCleavage
noneFracture
conchoidal to unevenSpecific Gravity
3.1Colors
red, orange, yellow, green, purple, brown, black, pink, colorlessTransparency
transparent to opaqueType Locality
Worldwide; notable occurrences include Garnet Ledge (Alaska, USA), India, Brazil, Sri Lanka, South Africa, USA (Idaho, Arizona, North Carolina).Mineral Group
silicatesUses
jewelry, abrasive, waterjet cutting, collector specimensAssociated Minerals
quartz, mica, feldspar, kyanite, stauroliteRarity
commonGeological Context
Garnets are characteristic minerals of metamorphic rocks, forming under high pressure and temperature conditions during regional metamorphism of pelitic sediments, and can also be found in some igneous rocks like granite and peridotite.
