Garnet (Almandine)

Almandine, Fe3Al2Si3O12

Rock Type: mineral

Garnet (Almandine)

Physical Properties

Hardness: 6.5-7.5. Color: Deep red to reddish-brown. Luster: Vitreous to resinous. Crystal structure: Isometric. Cleavage: None (conchoidal fracture). Specific Gravity: 3.5-4.3.

Formation & Geological History

Formed in metamorphic rocks such as mica schists and gneisses through the high-pressure, high-temperature metamorphism of clay-rich sedimentary rocks.

Uses & Applications

Commonly used as a gemstone in jewelry, especially when cut into cabochons. Also used industrially as an abrasive for sandblasting and waterjet cutting.

Geological Facts

Almandine is the most common variety of garnet and has been used in jewelry for thousands of years. It was particularly popular in the Victorian era.

Field Identification & Locations

Identify by its deep red color and high hardness. It is typically found in metamorphic terrain; look for twelve-sided crystals (dodecahedrons) in rocky outcrops.

Identified on: 5/6/2026

Mode: Standard