mineral

Amethyst

Silicon dioxide with iron impurities (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: Purple/Violet, Luster: Vitreous (glassy), Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified June 28, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple/Violet, Luster: Vitreous (glassy), Crystal structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) within igneous rocks. The purple color comes from gamma irradiation of trace iron atoms within the quartz crystal lattice.

Uses & applications

Primarily used in jewelry, as a semi-precious gemstone, for decorative ornaments, and highly valued by mineral collectors.

Geological facts

Amethyst was considered a 'Cardinal Gem' until large deposits were found in Brazil in the 1700s. Its name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its distinctive purple color and hexagonal crystal habit if raw. Found commonly in Brazil, Uruguay, and Madagascar. In the field, look for purple crystals inside basaltic geodes.