mineral

Amethyst Cluster

Silicon Dioxide (SiO2 with iron impurities)

Hardness: 7 on the Mohs scale. Color: Light to deep purple or violet. Luster: Vitreous/glassy. Crystal structure: Trigonal/Hexagonal prism topped with hexagonal pyramids. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Light to deep purple or violet
Luster: Vitreous/glassy

Identified July 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and volcanic cavity geodes where silica-rich hydrothermal solutions precipitate quartz crystals containing trace iron impurities that are irradiated by natural gamma rays.

Uses & applications

Popular as a decorative mineral specimen, gemstone for jewelry, cabochons, carved ornaments, and widely used in crystal healing and geological collection.

Geological facts

Amethyst is the purple variety of quartz and is the birthstone for February. Ancient Greeks believed it protected against drunkenness, deriving its name from 'amethystos' meaning 'not intoxicated'.

Field identification & locations

Identified by its distinctive purple color, crystal habit forming small pyradmid-like terminations in druzy clusters, and hardness of 7. Commonly found in Brazil, Uruguay, Madagascar, Zambia, and North Carolina.

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