mineral

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

Hardness: 7 on the Mohs scale. Color: Pale violet to deep purple, often with color zoning. Luster: Vitreous/Glassy. Crystal Structure: Hexagonal (Trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Pale violet to deep purple, often with color zoning
Luster: Vitreous/Glassy

Identified March 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings in geodes. The purple color is caused by natural irradiation of trace trivalent iron (Fe3+) in the quartz structure. Significant deposits range from Cretaceous to modern geological formations.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces), as decorative specimens, and in metaphysical practices. Historically used for drinking vessels.

Geological facts

Amethyst was considered one of the 'cardinal gems' until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone protected its owner from drunkenness.

Field identification & locations

Identify by its distinctive purple color and lack of cleavage (it breaks like glass). Often found in basaltic rocks or volcanic geodes. Major sources include Brazil, Uruguay, Zambia, and Ontario, Canada.

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