mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale; Color: purple to violet; Luster: vitreous (glassy); Crystal structure: Hexagonal (Trigonal); Cleavage: none; Specific gravity: 2.63 - 2.65

Hardness: 7 on Mohs scale
Color: purple to violet
Luster: vitreous (glassy)

Identified May 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: purple to violet; Luster: vitreous (glassy); Crystal structure: Hexagonal (Trigonal); Cleavage: none; Specific gravity: 2.63 - 2.65

Formation & geological history

Formed in igneous and metamorphic environments, typically within geodes or volcanic rocks where silica-rich fluids cool and crystallize over millions of years, often in Cenozoic or Mesozoic formations.

Uses & applications

Primarily used in jewelry, ornamental carvings, crystal healing, and as a popular decorative gemstone for collectors.

Geological facts

The purple color comes from irradiation, iron impurities, and the presence of trace elements. It was once considered as valuable as diamonds until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identified by its distinctive purple hue and hexagonal crystal habits. Common locations include Brazil, Uruguay, Zambia, and South Korea. Collectors look for deep violet saturation and clarity.