mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

AI-generated identification · may be incorrect

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

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

Identified March 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes. Its purple hue is caused by natural irradiation of trace amounts of iron within the crystal structure. It can be found in volcanic rocks dating from the Cretaceous period to the present.

Uses & applications

Predominantly used as a gemstone in jewelry (rings, necklaces, earrings), as decorative specimens for mineral collectors, and in metaphysical/holistic practices.

Geological facts

Amethyst was considered one of the 'Cardinal Gems' until large deposits were found in Brazil. The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was once believed to prevent drunkenness.

Field identification & locations

Identify in the field by its distinct purple translucency and characteristic hexagonal points (if not tumbled). It will scratch glass but cannot be scratched by a steel knife. Common locations include Brazil, Uruguay, Madagascar, and Ontario, Canada.