mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness 7 on Mohs scale; Color ranges from light lavender to deep violet; Vitreous (glassy) luster; Hexagonal/Trigonal crystal system; Conchoidal fracture; No cleavage.

Identified July 21, 2026More mineral →

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Physical properties

Hardness 7 on Mohs scale; Color ranges from light lavender to deep violet; Vitreous (glassy) luster; Hexagonal/Trigonal crystal system; Conchoidal fracture; No cleavage.

Formation & geological history

Forms in volcanic rocks, specifically inside geodes and cavities where silica-rich hydrothermal fluids crystallize over time. Formation can take millions of years.

Uses & applications

Primarily used in jewelry (faceting, beads, cabochons), ornamental decoration, and as a popular specimen for mineral collectors.

Geological facts

The purple color comes from irradiation, iron impurities, and the presence of trace elements. It was once considered one of the five cardinal gemstones alongside diamonds and rubies until large deposits were found in Brazil.

Field identification & locations

Identify by its characteristic purple hue and quartz-like hardness (can scratch glass). Found globally, with major deposits in Brazil, Uruguay, Zambia, and South Korea.