mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Deep purple to violet
Luster: Vitreous (glass-like)

Identified July 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Deep purple to violet; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed inside hydrothermal veins, geodes, and cavities in igneous rocks through the precipitation of silica-rich solutions under low-temperature conditions.

Uses & applications

Widely used as a gemstone in jewelry, ornamental carvings, crystal healing practices, and mineral collection.

Geological facts

The deep purple color comes from irradiation of trace amounts of trivalent iron (Fe3+) in the crystal structure. Ancient Greeks believed amethyst could prevent drunkenness.

Field identification & locations

Identified by its distinctive purple color, hardness (scratches glass, cannot be scratched by steel), and conchoidal fracture. Commonly found in Brazil, Uruguay, Zambia, Madagascar, and Russia.