mineral

Amethyst (Quartz variety)

Amethyst - SiO2 (Silicon Dioxide with Iron impurities)

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/Glassy, Crystal structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified April 12, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to violet, Luster: Vitreous/Glassy, Crystal structure: Hexagonal (trigonal), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes. Purple coloration results from gamma irradiation and the presence of trace amounts of iron within the quartz crystal lattice.

Uses & applications

Mostly used for jewelry (gemstones), ornamental carvings, and as a popular mineral specimen for collectors.

Geological facts

Amethyst was considered a 'Precious Stone' 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 by its distinctive purple hue, hardness of 7 (can scratch glass), and hexagonal crystal prism shapes. Commonly found in Brazil, Uruguay, and Madagascar.

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