mineral

Amethyst

Quartz (Silicon Dioxide) with Ferric Iron impurities - SiO2

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

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

Identified March 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. Its purple hue is caused by gamma irradiation of trivalent iron (Fe3+) impurities. Found in volcanic rocks ranging from Cenozoic to Precambrian ages.

Uses & applications

Predominantly used as a gemstone in jewelry, decorative carvings, and as 'curative' or spiritual crystals in alternative medicine. Industrially, it is used for high-end abrasive sandblasting or as an architectural stone in rare cases.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones along with diamond, ruby, sapphire, and emerald. Legend says the Greek god Bacchus created it from a maiden turned to stone.

Field identification & locations

Identify in the field by its distinct purple color, 6-sided prismatic crystals, and lack of true cleavage. Commonly found in Brazil, Uruguay, South Korea, and the Thunder Bay region of Canada.