mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: light to deep purple, Luster: vitreous (glass-like), Crystal structure: hexagonal (trigonal), Cleavage: none, Specific gravity: 2.65

Identified June 8, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: light to deep purple, Luster: vitreous (glass-like), Crystal structure: hexagonal (trigonal), Cleavage: none, Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of volcanic rocks. The purple color is caused by irradiation of trivalent iron impurities within the silicon dioxide structure.

Uses & applications

Predominantly used as a gemstone in jewelry, for decorative items, and in metaphysical or mineral collections.

Geological facts

Amethyst is the birthstone for February. The name comes from the Greek word 'amethystos', meaning 'not drunken', as ancient Greeks believed it protected the wearer from intoxication.

Field identification & locations

Identify by its distinct purple hue, glass-like luster, and lack of cleavage. It is commonly found in Brazil, Uruguay, Africa, and North America (especially Ontario and Arizona).