mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal system: hexagonal/trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65

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

Identified July 8, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: light to deep purple; Luster: vitreous (glassy); Crystal system: hexagonal/trigonal; Cleavage: none (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in geothermal environments, often inside basaltic geodes or hydrothermal veins when silica-rich water cools, enriched by trace amounts of iron and natural irradiation over millions of years.

Uses & applications

Highly valued as a semi-precious gemstone in jewelry, used for ornamental carvings, and widely collected as mineral specimens for interior decor and metaphysical purposes.

Geological facts

The purple color comes from iron irradiation; it was once considered one of the five cardinal gemstones until large deposits were found in Brazil in the 1700s, making it more affordable.

Field identification & locations

Identify by its six-sided crystal terminations and purple hue. Found globally, with major deposits in Brazil and Uruguay. Collectors look for deep saturation and crystal clarity.