mineral

Amethyst

Silicon Dioxide (Quartz variety), SiO2

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Purple, violet, to pale lilac; Luster: Vitreous (glassy); Crystal structure: Trigonal (hexagonal system); Cleavage: None, exhibits conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, to pale lilac
Luster: Vitreous (glassy)

Identified August 3, 2026More mineral →

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Physical properties

Formation & geological history

Formed within gas cavities (vugs or geodes) in volcanic rocks through the deposition of silica-rich hydrothermal fluids containing trace amounts of iron, which are irradiated over millions of years.

Uses & applications

Widely used in jewelry, as a collector's specimen, in lapidary arts, and historically as a talisman or decorative gemstone.

Geological facts

Amethyst was once considered one of the cardinal gemstones of high value until large deposits were discovered in Brazil. Its purple color comes from iron impurities combined with natural irradiation.

Field identification & locations

Easily identified by its distinct purple coloration and hexagonal crystal points growing from a matrix. Commonly found in Brazil, Uruguay, Zambia, and the USA.