mineral

Garnet crystals

Garnet-group silicates, likely almandine (Fe₃Al₂Si₃O₁₂)

AI-generated identification · may be incorrect

Dark red-brown to nearly black, vitreous to resinous luster, commonly dodecahedral or irregular crystals; Mohs hardness 6.5–7.5, no cleavage, granular fracture, specific gravity about 3.5–4.3.

Identified August 28, 2026More mineral →

Explore Garnet crystals in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Dark red-brown to nearly black, vitreous to resinous luster, commonly dodecahedral or irregular crystals; Mohs hardness 6.5–7.5, no cleavage, granular fracture, specific gravity about 3.5–4.3.

Formation & geological history

Garnet typically forms in metamorphic rocks such as schist and gneiss during regional metamorphism, though some varieties occur in igneous rocks and placers. Individual crystals may be Paleozoic to Precambrian depending on locality.

Uses & applications

Used as an abrasive in sandpaper, waterjet cutting, filtration, and blasting; transparent gem-quality garnet is used in jewelry. These appear primarily as mineral specimens or abrasive-grade fragments.

Geological facts

The dark color and blocky, high-relief crystals are consistent with almandine, though identification from a photograph is not definitive; associated pale grains may be quartz or feldspar.

Field identification & locations

Look for hard, glassy, cleavage-free crystals that can scratch glass and resist a steel knife. Common sources include metamorphic terrains in India, Madagascar, the United States, Czechia, and Sri Lanka.