mineral

Amethyst

Amethyst (Silicon Dioxide with iron impurities, SiO2)

Hardness: 7 on the Mohs scale. Color: Pale lilac to deep reddish-purple. Luster: Vitreous (glass-like). Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Pale lilac to deep reddish-purple
Luster: Vitreous (glass-like)

Identified March 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) within igneous and metamorphic rocks. The purple color is caused by natural irradiation of trace iron impurities within the quartz crystal lattice. Specimens can range from thousands to millions of years old.

Uses & applications

Primarily used in jewelry (faceting, cabochons), ornamental carvings, and as a popular mineral specimen for collectors. In industry, high-quality quartz is used in electronics, though amethyst is mostly valued for its aesthetic appeal.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones alongside diamond, ruby, emerald, and sapphire. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief that it protected the wearer from drunkenness.

Field identification & locations

Identify by its characteristic purple color, high hardness (it will scratch glass), and lack of cleavage (it breaks with smooth, curved surfaces). Major deposits are found in Brazil, Uruguay, Zambia, and Canada. Collectors look for deep saturation and clear transparency.

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