mineral

Amethyst

Silicon Dioxide (SiO2)

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 June 13, 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 basaltic geodes. Its purple color comes from irradiation of iron impurities within the quartz crystal lattice. Found in deposits ranging from millions to billions of years old.

Uses & applications

Primarily used in jewelry (faceting, cabochons, beads), as ornamental specimens for collectors, and in decorative items like bookends or tabletops.

Geological facts

It was considered one of the five cardinal gems until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the gem protected its owner from drunkenness.

Field identification & locations

Identify by its distinctive purple hue and hexagonal crystal shape in the rough. Common locations include Brazil, Uruguay, Zambia, and South Korea. Collectors should look for deep 'Siberian' purple with red/blue flashes.