mineral

Amethyst (Tumbled)

Quartz (Silicon Dioxide, SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Purple to deep violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple to deep violet
Luster: Vitreous (glassy)

Identified May 18, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple to deep violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in geodes or hydrothermal veins when silicon dioxide crystallizes in the presence of trace amounts of iron and natural irradiation over millions of years, often in volcanic rock cavities.

Uses & applications

Widely used in jewelry (rings, pendants), meditation stones, decorative home decor, and as a popular specimen for mineral collectors.

Geological facts

The purple color of amethyst was once believed to prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not drunken'. It is the birthstone for February.

Field identification & locations

Identify by its characteristic purple hue and glassy luster. Commonly found in Brazil, Uruguay, and Africa. Look for hexagonal crystal points or rounded, water-worn pebbles in stream beds near volcanic regions.

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