mineral

Quartz (Amethyst variety)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Purple to pale lavender, Luster: Vitreous/Glassy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified April 10, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to pale lavender, Luster: Vitreous/Glassy, Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes. The purple color comes from irradiation of iron impurities in the silica structure. Found in igneous and metamorphic environments.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative carvings, and highly valued by mineral collectors for its aesthetic appeal.

Geological facts

The name amethyst comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness. It was once considered one of the five cardinal gems.

Field identification & locations

Identify by its purple hue and ability to scratch glass. Commonly found in Brazil, Uruguay, and Africa. To identify in the field, look for hexagonal crystal points and conchoidal fractures.