mineral

Amethyst (Tumbled Quartz)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Purple, violet, lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

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

Identified May 23, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple, violet, lavender; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed in igneous or metamorphic environments, typically inside volcanic geodes. The purple color is caused by irradiation of iron impurities within the silicon dioxide structure. Formation can take millions of years.

Uses & applications

Widely used in jewelry (rings, necklaces, earrings), as decorative specimens, and in spiritual/holistic wellness practices as a healing crystal.

Geological facts

Amethyst was as valuable as diamonds until large deposits were discovered in Brazil in the 19th century. The name comes from the Greek 'amethystos,' meaning 'not intoxicated.'

Field identification & locations

Identify by its distinct purple hue and glassy luster. Often occurs in geodes or as tumbled stones. Common locations include Brazil, Uruguay, and Zambia.