mineral

Amethyst

Amethyst (SiO2 with iron impurities)

Hardness: 7 (Mohs scale), Color: light to dark purple/violet, Luster: Vitreous, Crystal structure: Hexagonal (trigonal), Cleavage: none (conchoidal fracture), Specific Gravity: 2.65

Identified June 1, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: light to dark purple/violet, Luster: Vitreous, Crystal structure: Hexagonal (trigonal), Cleavage: none (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and volcanic cavities (geodes). The purple color is caused by irradiation of trivalent iron (Fe3+) in the quartz structure. Most specimens found today are from the Cretaceous period.

Uses & applications

Primary use is in jewelry and as a gemstone. It is also highly popular as a specimen for mineral collectors and used in decorative items or metaphysical practices.

Geological facts

The name comes from the ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness. It is the birthstone for February.

Field identification & locations

Identify by its characteristic purple color and hexagonal prism shapes. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for transparent to translucent purple crystals in volcanic rock cavities.