metamorphic

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

AI-generated identification · may be incorrect

Hardness: 7-7.5 (Mohs scale); Color: Deep brownish-red to black; Luster: Vitreous to resinous; Crystal structure: Isometric (dodecahedral); Cleavage: None; Specific gravity: 4.31

Hardness: 7-7
Color: Deep brownish-red to black
Luster: Vitreous to resinous

Identified July 12, 2026More metamorphic →

Explore Almandine Garnet in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7-7.5 (Mohs scale); Color: Deep brownish-red to black; Luster: Vitreous to resinous; Crystal structure: Isometric (dodecahedral); Cleavage: None; Specific gravity: 4.31

Formation & geological history

Forms during regional metamorphism of clay-rich sedimentary rocks like shale, commonly found in mica schists and gneisses.

Uses & applications

Used primarily as an abrasive in sandblasting and water-jet cutting; high-quality specimens are used in jewelry.

Geological facts

Almandine is the most common member of the garnet group. The name is a corruption of Alabanda, a city in Asia Minor where these stones were historically cut.

Field identification & locations

Identify in the field by its characteristic dodecahedral crystal shape and extreme hardness. Often found as porphyroblasts in metamorphic schists in locations like the Adirondack Mountains or the Alps.