mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified July 2, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; 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 or as linings inside volcanic geodes. The purple color comes from irradiation of iron impurities within the quartz crystal lattice.

Uses & applications

Widely used in jewelry (facets, beads, cabochons), as decorative crystal clusters, and in spiritual/metaphysical practices.

Geological facts

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

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal terminations. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep, uniform color (Siberian hue) and clarity.