mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with Iron impurities)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/Glassy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous/Glassy

Identified April 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous/Glassy; Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in hydrothermal veins or as linings within gas cavities (geodes) in volcanic rocks. The purple color is caused by gamma irradiation of trivalent iron impurities and charge transfer within the crystal lattice.

Uses & applications

Predominantly used as a gemstone in jewelry, as decorative display specimens, and in spiritual/holistic practices. Also historically used for intaglio carving.

Geological facts

In ancient Greece, it was believed that wearing or drinking from a vessel of amethyst could prevent intoxication. It is the official birthstone for February and is the state gemstone of South Carolina.

Field identification & locations

Identify by its six-sided crystal points and characteristic purple hue. Often found in basalt geodes. Major deposits are located in Brazil, Uruguay, Madagascar, and Russia.

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