mineral
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Hardness: 6.5-7.5 on Mohs scale. Color: Deep red to reddish-brown, often appearing black in large crystals. Luster: Vitreous to resinous. Crystal structure: Isometric (dodecahedral). Specific gravity: 3.5-4.3.
- Hardness
- 6
- Luster
- Vitreous to resinous
Identified More mineral →
Explore Garnet (Almandine) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7.5 on Mohs scale. Color: Deep red to reddish-brown, often appearing black in large crystals. Luster: Vitreous to resinous. Crystal structure: Isometric (dodecahedral). Specific gravity: 3.5-4.3.
Formation & geological history
Formed primarily in metamorphic rocks like mica schists, gneisses, and amphibolites under high pressure and temperature. It is also found in some igneous rocks and as a heavy mineral in alluvial deposits.
Uses & applications
Used widely as a gemstone in jewelry and as an industrial abrasive for waterjet cutting, sandblasting, and water filtration.
Geological facts
Garnet is the birthstone for January. Almandine is the most common member of the garnet group. Some garnets exhibit an optical phenomenon known as asterism (star-like reflection).
Field identification & locations
Identify in the field by its characteristic 12-sided (dodecahedral) crystal shape, high hardness, and translucency when held to light. Commonly found in metamorphic terrains such as the Adirondack Mountains or the Alps.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic