mineral

Amethyst

Quartz (SiO2)

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal Structure: Trigonal, hexagonal prism; Cleavage: None; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple to violet
Luster: Vitreous

Identified August 3, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple to violet; Luster: Vitreous; Crystal Structure: Trigonal, hexagonal prism; Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and cavities (vugs/geodes) within volcanic rocks, often through the cooling of silica-rich solutions containing trace iron impurities subjected to natural irradiation.

Uses & applications

Used widely in jewelry, gemstone carving, decorative items, and mineral collecting.

Geological facts

Amethyst was historically considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil during the 19th century.

Field identification & locations

Easily identified by its distinct purple coloration and conchoidal fracture. Found globally, with significant deposits in Brazil, Uruguay, Zambia, and the United States.