mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 (Mohs), Color: Purple to violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs), Color: Purple to violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks, often where silica-rich minerals crystallize at medium-to-low temperatures. Its purple color comes from irradiation and iron impurities.

Uses & applications

Widely used for jewelry (faceted or cabochon), ornamental carvings, crystal healing, and as home decor/specimens for collectors.

Geological facts

Amethyst is the birthstone for February. Ancient Greeks believed it could prevent intoxication; the word comes from the Greek 'amethystos,' meaning 'not drunken.'

Field identification & locations

Look for its signature purple color and lack of cleavage (breaks like glass). Commonly found in Brazil, Uruguay, and Africa. Collectors should check for pleochroism and natural inclusions.