Glittering Stones >> Semi precious stones >> Garnet

Semi Precious Stone Garnet

The garnet group of minerals usually shows crystals with a habit of rhombic dodecahedrons and also with trapezohedrons. They are nesosilicates with the same general formula, A3B2 (SiO4)3. The chemical elements in the garnet include calcium, magnesium, aluminum, iron2+, iron3+, chromium, manganese, and also titanium. Garnets show no cleavage and a dodecahedral parting. Fracture is a concordat to uneven; some varieties are very tough and are also very valuable for abrasive purposes. Hardness is 6.5 - 8.5, specific gravity is 3.1 - 4.3, luster is vitreous to resinous, and that they can be transparent to opaque.

Historical Facts of Garnet

Refractive Index: 1.72 - 1.94

Crystal System: Cubic

Chemical Composition: X3Y2(SiO4)3

Mohs Scale Hardness: 6.0 - 7.5

Major Varieties: Almandine, Pyrope, Spessartite, Andradite, Grossular, Uvarovite

Colors: Red, orange, yellow, green, blue, purple, brown, black, pink and colorless

Occurrence: Macon County, North Carolina, United States, Russia, Turkey

Gem Jewelry Garnet