mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous

Identified June 27, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or geodes within volcanic rocks when silica-rich water cools. The purple color is caused by irradiation of trivalent iron impurities. These can range from hundreds of millions to billions of years old.

Uses & applications

Primarily used in jewelry, as gemstone specimens for collectors, and in decorative items. Historically believed to prevent intoxication.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' alongside diamond and ruby, until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its six-sided prismatic crystal shape and purple zoning. Commonly found in Brazil, Uruguay, and Madagascar. Collectors look for deep saturation and clarity.