mineral

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

AI-generated identification · may be incorrect

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

Hardness: 7 on Mohs scale
Color: Pale lilac to deep purple
Luster: Vitreous

Identified March 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) within igneous and metamorphic rocks. The purple color results from irradiation of trivalent iron (Fe3+) impurities within the quartz lattice. Most commercial deposits are found in Mesozoic-aged basaltic rocks.

Uses & applications

Primarily used in jewelry as a gemstone (faceted or cabochon), in ornamental carvings, and widely collected by mineral enthusiasts for metaphysical or decorative purposes.

Geological facts

Amethyst was considered one of the 'Cardinal Gems' alongside diamond and ruby until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness.

Field identification & locations

Identify in the field by its distinct purple hue, hexagonal prism shape with pyramidal terminations, and its ability to scratch glass. Major global sources include Brazil (Rio Grande do Sul), Uruguay, Zambia, and Ontario, Canada.