Garnet

Physical Properties

Hardness: 6.5-7.5. Color: Deep reddish-brown to black. Luster: Vitreous to resinous. Crystal structure: Isometric (dodecahedral). Cleavage: None. Specific gravity: 3.5-4.3.

Formation & Geological History

Formed primarily in metamorphic rocks like schist and gneiss under high pressure and temperature; also found in some igneous rocks. Ages range from Precambrian to Cenozoic.

Uses & Applications

Used as industrial abrasives (sandblasting, waterjet cutting), gemstones in jewelry, and decorative polished spheres or ornaments.

Geological Facts

The name 'garnet' comes from the Latin 'granatus' (meaning seed/pomegranate). Garnet has been used as a gemstone since the Bronze Age and is the birthstone for January.

Field Identification & Locations

Identify in the field by its crystal habit (dodecahedron), high hardness, and lack of cleavage. Often found in micaceous schists or as heavy mineral sand in stream beds.

Identified on: 4/29/2026

Mode: Standard