mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

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

Identified May 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within igneous volcanic rocks like basalt. The purple color is caused by irradiation of iron impurities.

Uses & applications

Primarily used in jewelry (as a semi-precious gemstone), decorative carvings, and as a popular mineral specimen for collectors.

Geological facts

Amethyst was as expensive as diamonds until large deposits were found in Brazil in the 19th century. Its name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple color and hexagonal prismatic crystals if untumbled. Found commonly in Brazil, Uruguay, Zambia, and South Korea. Look for transparent to translucent clarity.