mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

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

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

Identified June 3, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins or cavities (geodes) within igneous and metamorphic rocks. Generally formed during the cooling of volcanic lava; age varies by deposit from millions to billions of years.

Uses & applications

Used primarily in jewelry (facets, cabochons), beads, and as decorative collector specimens. Historically used for amulets and carvings.

Geological facts

The name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. It is the birthstone for February.

Field identification & locations

Identify by its distinct purple color and 6-sided crystal habits when raw; it will scratch glass but cannot be scratched by a steel knife. Common locations include Brazil, Uruguay, and Zambia.