mineral

Amethyst

Amethyst (Silicon Dioxide containing trace Iron impurities, SiO2)

Hardness: 7 (Mohs scale); Color: Purple to deep violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple to deep violet
Luster: Vitreous/Glassy

Identified April 9, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple to deep violet; Luster: Vitreous/Glassy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as geodes in igneous volcanic rocks (basalt). The purple color results from irradiation of trivalent iron impurities (Fe3+) within the crystal lattice.

Uses & applications

Primarily used in jewelry (faceting and cabochons), as decorative display specimens for collectors, and in metaphysical/spiritual practices.

Geological facts

Amethyst was considered a cardinal gem and was as valuable as diamonds until large deposits were found in Brazil in the 19th century. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief it protected owners from drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal prism shapes. In the field, look for quartz with conchoidal (shell-like) fractures that cannot be scratched by a steel knife. Major deposits are in Brazil, Uruguay, and Zambia.

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