mineral

Amethyst

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified July 21, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within volcanic rock. The purple color is caused by irradiation of iron impurities within the quartz crystal structure.

Uses & applications

Primarily used as a gemstone in jewelry, for decorative ornaments, and highly valued by mineral collectors for its metaphysical properties and aesthetic appeal.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness. It is the official birthstone for February.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal habit. It is frequently found in Brazil, Uruguay, and Africa. Look for glassy luster and the absence of cleavage in crystal clusters.