mineral

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Hardness: 7 on the Mohs scale; Color: Purple, violet, to pale lavender; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Purple, violet, to pale lavender
Luster: Vitreous (glass-like)

Identified February 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within volcanic rock. The purple color comes from irradiation of iron impurities in the quartz. They can range from millions to billions of years old depending on the host rock.

Uses & applications

Primary use is in jewelry (faceted gemstones, beads, cabochons) and as decorative specimens/ornamental objects. It is also highly popular for mineral collecting and metaphysical use.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. It is the birthstone for February and was once considered a 'Cardinal Gem' on par with diamonds and rubies before large deposits were found in Brazil.

Field identification & locations

Identify by its characteristic purple color, glass-like luster, and absence of cleavage surfaces. Often found in Brazil, Uruguay, Madagascar, and the United States (Arizona/North Carolina). Look for hexagonal crystal terminations in geodes.

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