mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal structure: hexagonal/trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: light to deep purple
Luster: vitreous (glassy)

Identified May 10, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal structure: hexagonal/trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed in geodes and hydrothermal veins via precipitation from silica-rich fluids. The purple color is caused by trace amounts of iron influenced by natural irradiation in the surrounding rock.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative items, and as a popular mineral specimen for collectors.

Geological facts

Ancient Greeks believed amethyst could prevent drunkenness. The name comes from the Greek word 'amethystos', meaning 'not intoxicated'. Until the 18th century, it was considered one of the five cardinal gemstones alongside diamonds and rubies.

Field identification & locations

Identify by its distinct purple hue, glass-like luster, and hexagonal crystal shapes. Commonly found in Brazil, Uruguay, and various locations in Africa and North America.

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