mineral

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

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

Hardness: 7 on the Mohs scale
Color: Deep purple to pale lavender
Luster: Vitreous (glassy)

Identified May 13, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) of igneous and metamorphic rocks. The purple color is caused by irradiation of iron impurities within the quartz crystal lattice. It can form in various geological eras where silica-rich fluids permeate rock cavities.

Uses & applications

Predominantly used in jewelry (faceting or cabochons), ornamental carvings, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was once considered as valuable as diamonds until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness.

Field identification & locations

Identify in the field by its characteristic purple hue, hexagonal crystal points (if present), and ability to scratch glass while remaining resistant to steel files. Frequently found in volcanic basalt cavities in places like Brazil, Uruguay, and Arizona.