mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: light to deep purple (due to irradiation and iron), Luster: Vitreous, Crystal structure: Trigonal (Hexagonal prisms), Cleavage: None/Conchoidal fracture, Specific gravity: 2.65

Identified July 12, 2026More mineral →

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Physical properties

Formation & geological history

Forms in geodes or hydrothermal veins within igneous and metamorphic rocks. Most large-scale deposits are associated with volcanic basalt flows or pegmatites.

Uses & applications

Primarily used as a gemstone in jewelry (faceting, cabochons), for decorative carvings, and highly popular as display specimens for collectors.

Geological facts

Amethyst was considered a precious stone comparable to diamond until massive deposits were discovered in Brazil in the 18th century. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple hue and hexagonal crystal habitat. Common in Brazil, Uruguay, and Africa. Look for prismatic crystals with pyramid-shaped terminations often found in cavities of volcanic rock.