mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: Purple, violet, lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

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

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings in hollow volcanic rocks (geodes). The purple color is caused by natural irradiation of trace iron impurities within the quartz crystal lattice.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was considered a precious stone in ancient times, comparable to Diamond and Ruby, until large deposits were discovered in Brazil in the 19th century. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit when raw; it will scratch glass and lacks cleavage. Common locations include Brazil, Uruguay, Zambia, and Ontario, Canada.