mineral

Amethyst

Amethyst (SiO2)

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

Identified June 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins and basaltic geodes through the cooling of silica-rich solutions. The purple color is caused by trace amounts of iron and natural irradiation within the earth's crust. Most major deposits are in Brazil and Uruguay.

Uses & applications

Widely used for jewelry (birthstone for February), decorative ornaments, crystal healing practices, and as a popular mineral specimen for collectors.

Geological facts

Amethyst is a variety of quartz. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as the Greeks believed the gem could prevent drunkenness.

Field identification & locations

Identified by its distinctive purple hue and hexagonal crystal form (terminating in six-sided pyramids). Look for it in geodes or volcanic rock outcrops. Frequently found in Uruguay, Brazil, and Arizona.