mineral

Amethyst (as part of a multi-stone bracelet)

Silicon Dioxide (SiO2) with iron impurities

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

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous (glassy)

Identified January 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple/Violet; 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. It crystallizes from silica-rich solutions at low to moderate temperatures. It can be found in rocks from various geological ages, often concentrated in volcanic cavaties.

Uses & applications

Primarily used as a gemstone in jewelry, decorative carvings, and by mineral collectors. In industry, high-quality quartz has historical uses in watchmaking and electronics, though amethyst is typically reserved for aesthetics.

Geological facts

The purple color comes from irradiation, iron impurities, and the presence of trace elements. Historically, Ancient Greeks believed it could prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its distinct purple color and hexagonal crystal habit. Found globally with major deposits in Brazil, Uruguay, and Zambia. Collectors should look for vibrant saturation and absence of visible inclusions (though 'tiger stripes' are common in natural stones).

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