mineral

Amethyst Cluster

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Deep purple to violet. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal prismatic). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Deep purple to violet
Luster: Vitreous (glassy)

Identified July 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Deep purple to violet. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal prismatic). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and volcanic rocks (geodes) when silica-rich fluid precipitates crystals inside rock cavities, with natural gamma irradiation acting on trace iron impurities to create the purple color.

Uses & applications

Used widely in jewelry, lapidary arts, mineral specimen collecting, home decor, and crystal healing practices.

Geological facts

Amethyst was considered one of the cardinal gems until large deposits were found in Brazil in the 19th century. Ancient Greeks believed it prevented drunkenness.

Field identification & locations

Identified by its distinctive purple color, hardness of 7 (scratches glass), and six-sided crystal terminations. Major deposits are located in Uruguay, Brazil, Madagascar, and Zambia.