mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Violet to dark purple. Luster: Vitreous/glassy. Crystal structure: Hexagonal/trigonal. Cleavage: None (conchoidal fracture). Specific gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Violet to dark purple
Luster: Vitreous/glassy

Identified July 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Violet to dark purple. Luster: Vitreous/glassy. Crystal structure: Hexagonal/trigonal. Cleavage: None (conchoidal fracture). Specific gravity: ~2.65.

Formation & geological history

Forms in hydrothermal veins and cavities (geodes) within volcanic rocks when silica-rich fluids cool and crystallize in the presence of trace amounts of ferric iron (Fe3+) combined with natural irradiation.

Uses & applications

Widely used as a gemstone in jewelry (rings, necklaces, earrings), ornamental carvings, crystal healing, and as decorative geode/cluster display specimens for collectors.

Geological facts

Amethyst is the official birthstone for February. Ancient Greeks believed wearing or drinking from cups made of amethyst would prevent intoxication, which is where its name originates (Greek 'amethystos' meaning 'not intoxicated').

Field identification & locations

Identified by its distinctive purple color, hardness (scratches glass, cannot be scratched by steel knife), and crystal form. Major sources include Brazil, Uruguay, Madagascar, Zambia, and Russia.