mineral

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified March 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or cavities within volcanic rocks (basalt) and granite. The color is caused by irradiation, iron impurities, and the presence of trace elements. Age varies by location, from Recent to over 100 million years.

Uses & applications

Primarily used in jewelry (faceting and cabochons), ornamental carvings, crystal healing practices, and as mineral specimens for collectors.

Geological facts

Amethyst is the birthstone for February. It was considered as valuable as diamonds until the early 19th century when large deposits were discovered in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify in the field by its purple color and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for hexagonal crystal points or geodes inside volcanic rock outcrops.