mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

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

Hardness: 7 on Mohs scale
Color: Pale lavender to deep violet
Luster: Vitreous (glassy)

Identified March 22, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or volcanic geodes when silica-rich water cools. The purple color comes from irradiation of iron impurities. They can form in rocks ranging from millions to billions of years old.

Uses & applications

Primarily used in jewelry (faceting and cabochons), ornamental carvings, and as popular specimens for mineral collectors and metaphysical practitioners.

Geological facts

Until the discovery of large deposits in Brazil in the 19th century, amethyst was as expensive as ruby and emerald; it was historically one of the 'Cardinal Gems'.

Field identification & locations

Identify in the field by its distinct purple hue and lack of cleavage. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for saturated color and clarity.

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