mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Purple, violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified July 17, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is caused by trace amounts of iron and natural irradiation within the earth.

Uses & applications

Popular in jewelry, holistic practices, and as a collector's mineral specimen. Most prized when it has deep purple coloring.

Geological facts

Formerly considered one of the 'Cardinal Gems' alongside diamond, ruby, sapphire, and emerald until large deposits were found in Brazil in the 1800s. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple color and hexagonal crystal terminations. Commonly found in Brazil, Uruguay, and Madagascar. Collectors look for deep shade saturation and lack of visible inclusions.