mineral

Amethyst

SiO2 (Silicon Dioxide) - Purple variety of Quartz

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

Hardness: 7 on the Mohs scale
Color: Violet to deep purple
Luster: Vitreous (glassy)

Identified March 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins and basaltic geodes through volcanic activity. The purple color comes from irradiation, iron impurities, and the presence of trace elements. Found in rocks ranging from Cenozoic to Precambrian ages.

Uses & applications

Primary use is in jewelry (faceted gemstones, beads) and as a lapidary material. It is also highly valued by mineral collectors for decorative specimens and metaphysical purposes.

Geological facts

Amethyst was once considered a 'Cardinal Gem' on par with Diamond and Ruby until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its hexagonal crystal habit, lack of cleavage, and characteristic purple hue. Common locations include Brazil, Uruguay, Zambia, and Ontario, Canada. High-quality specimens have deep purple saturation with red or blue flashes.

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