mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified May 31, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is caused by irradiation of trivalent iron impurities (Fe3+) in the quartz structure.

Uses & applications

Highly popular in jewelry including rings, necklaces, and earrings. Widely used for decorative display specimens, crystal healing practices, and as birthstone for February.

Geological facts

The name comes from the ancient Greek word 'amethystos', meaning 'not intoxicated', as Greeks believed the stone could prevent drunkenness. Until the 18th century, it was considered one of the most precious gemstones alongside diamond and ruby.

Field identification & locations

Identify by its distinct purple hue and quartz-like hardness (scratches glass). Can be found globally with major deposits in Brazil and Uruguay. Collectors look for deep saturation and clarity.