mineral

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Pale violet to deep purple
Luster: Vitreous (glassy)

Identified June 30, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is caused by natural irradiation of iron impurities within the quartz crystal lattice.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces), high-end interior decoration, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones on par with diamonds and rubies. The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify by its distinct purple hue and hexagonal prismatic crystal shape terminating in a pyramid. Commonly found in Brazil, Uruguay, and Zambia. In the field, look for volcanic basalt host rocks or vugs.