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 18, 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

Forms in hydrothermal veins and basaltic geodes. Its purple color is caused by natural irradiation of trace amounts of trivalent iron (Fe3+) in its quartz structure. Often found in volcanic cavities.

Uses & applications

Extensively used in jewelry (faceting and cabochons), as decorative display specimens, and in metaphysical collecting.

Geological facts

Amethyst was considered a precious stone in antiquity, rivaling diamonds, until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its six-sided prismatic crystals terminating in pyramids and its characteristic purple hue. Common in Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep saturation and good clarity.