mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

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

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

Identified July 20, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or as linings in cavities (geodes) within igneous rocks, particularly volcanic basalts. The purple color is caused by irradiation of trivalent iron impurities.

Uses & applications

Widely used as a gemstone in jewelry, for decorative household items, as a healing crystal in metaphysical practices, and as a popular mineral specimen for collectors.

Geological facts

Amethyst is the most valuable variety of quartz. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness.

Field identification & locations

Identify by its characteristic purple color and hexagonal habit if uncut. Common in Brazil, Uruguay, and Africa. Look for clear, vibrant purple areas and natural quartz fractures.