mineral

Amethyst (Tumbled/Water-worn)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, to pale lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, to pale lavender
Luster: Vitreous (glassy)

Identified May 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, to pale lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rocks where silica-rich fluids cooled over time. The purple color is caused by irradiation of trivalent iron (Fe3+) impurities and the presence of trace elements within the crystal lattice.

Uses & applications

Primarily used in jewelry, birthstone products (February), and as a popular specimen for collectors and holistic practices.

Geological facts

Amethyst was considered as valuable as diamonds until the 18th century when large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its distinctive purple hue and lack of cleavage. In the field, look for hexagonal crystal points or rounded, purple-tinted river pebbles. Common in Brazil, Uruguay, Zambia, and Ontario.