mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

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 July 18, 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 silica-rich hydrothermal veins and volcanic cavities (geodes). The purple color is caused by irradiation of iron impurities within the quartz structure. Typical ages range from millions to hundreds of millions of years.

Uses & applications

Primarily used in jewelry, as decorative collector specimens, and in metaphysical practices. Industrially, quartz is used in glassmaking and electronics.

Geological facts

Amethyst was considered a precious stone on par with diamonds until large deposits were found in Brazil. Its name comes from the Greek 'amethystos', meaning 'not intoxicated', due to a belief it prevented drunkenness.

Field identification & locations

Identify by its distinct purple hue and quartz-like hardness. Often found in basalt vugs in Brazil, Uruguay, and Zambia. Collectors look for deep saturation and clarity.