mineral

Almandine Garnet

Fe3Al2(SiO4)3

Hardness: 7-8.5 (Mohs), Color: Deep red to reddish-brown, Luster: Vitreous to resinous, Crystal Structure: Isometric (dodecahedron), Cleavage: None (conchoidal fracture), Specific Gravity: 4.3

Hardness: 7-8

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7-8.5 (Mohs), Color: Deep red to reddish-brown, Luster: Vitreous to resinous, Crystal Structure: Isometric (dodecahedron), Cleavage: None (conchoidal fracture), Specific Gravity: 4.3

Formation & geological history

Formed primarily in regionally metamorphosed rocks like mica schists, gneisses, and amphibolites where high pressure and heat allow for recrystallization. It can also be found in some igneous rocks.

Uses & applications

Commonly used as an abrasive in industrial sandblasting and water-jet cutting. Transparent, high-quality specimens are used in jewelry as gemstones.

Geological facts

Garnets are the birthstone for January. Almandine is the most common member of the garnet group and has been used in jewelry for thousands of years, notably by ancient Romans.

Field identification & locations

Identify in the field by its distinct crystal shape (dodecahedron), high hardness, and reddish color. It is common in metamorphic belts such as the New England area or the Alps.