mineral

Amethyst

SiO2 (Silicon Dioxide) - Purple variety of Crystalline Quartz

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

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings in geodes within igneous or metamorphic rocks. The purple color comes from iron impurities and natural irradiation. They are found in rocks of various ages, with massive deposits in Brazil and Uruguay dating back to the Cretaceous period.

Uses & applications

Primary use is in jewelry (faceted gemstones or cabochons) and as decorative specimens/geodes. Also used in crystal healing and metaphysical practices. Historically used to make drinking vessels.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect the wearer from drunkenness. It was considered one of the five cardinal gemstones until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identify in the field by its distinct purple color, 6-sided prismatic crystals ending in pyramids, and lack of cleavage. Common locations include Brazil, Uruguay, Zambia, and South Korea. For collectors, look for deep saturated color and high clarity.

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