mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Pale violet to deep purple; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale violet to deep purple
Luster: Vitreous

Identified July 14, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale violet to deep purple; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and basaltic geodes through the cooling of silica-rich solutions under moderate temperatures and pressures. Its color is derived from irradiation and iron impurities in the quartz structure.

Uses & applications

Primarily used as a gemstone in jewelry, for decorative carvings, and as a popular specimen for mineral collectors and crystal healers.

Geological facts

Amethyst was once considered as valuable as diamonds and rubies until large deposits were discovered in Brazil in the 1700s. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple hue and hexagonal crystal system if terminated. In the field, look for conchoidal (shell-like) fractures and the ability to scratch glass but not topaz. Found globally, specifically in Brazil, Uruguay, and Namibia.