mineral

Amethyst

Silicon Dioxide (SiO2), Quartz variety

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous (glassy); Crystal structure: Trigonal (hexagonal system); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple to violet
Luster: Vitreous (glassy)

Identified July 29, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous (glassy); Crystal structure: Trigonal (hexagonal system); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in gas cavities (vesicles) of volcanic rocks, hydrothermal veins, and metamorphic rocks where silica-rich fluids cool and precipitate crystalline quartz containing trace iron and subjected to natural irradiation.

Uses & applications

Widely used as a gemstone in jewelry, decorative ornaments, crystal healing, and mineral collections.

Geological facts

Amethyst was once considered as valuable as diamond, ruby, emerald, and sapphire until large deposits were discovered in Brazil. Its purple color comes from irradiation of iron impurities.

Field identification & locations

Easily identified by its distinctive purple color and quartz crystal form. Found worldwide, with notable deposits in Brazil, Uruguay, Zambia, and the United States.