mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

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

Identified June 13, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins or as linings within volcanic rock geodes. The purple color comes from irradiation of iron impurities within the quartz crystal structure as it grows in basaltic cavities.

Uses & applications

Extensively used in jewelry (faceting, beads, cabochons), carvings, decorative home ornaments, and as a popular specimen for mineral collectors.

Geological facts

Amethyst is the birthstone for February. In ancient times, Greeks believed it could prevent intoxication, which is why its name comes from the Greek word 'amethystos' meaning 'not drunk'.

Field identification & locations

Identified by its hexagonal crystal habit, 7 hardness, and distinct purple color. Commonly found in Brazil, Uruguay, and various locations in Africa and North America. In the field, look for purple crystals inside rounded, bumpy rock geodes.

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