mineral

Amethyst/Smoky Quartz Cluster

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: range from pale lavender to deep violet (if amethyst) or translucent gray/brown (if smoky). Luster: Vitreous/Glassy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Luster: Vitreous/Glassy

Identified March 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as mineral linings inside volcanic geodes. Natural irradiation or traces of iron impurities during crystalline growth create the distinct colors. Found across geological ages from millions to billions of years old.

Uses & applications

Extensively used in jewelry (faceted gemstones), interior decoration (large cathedral geodes), and as a popular specimen for metaphysical and mineral 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 characteristic six-sided pyramid-shaped crystal terminations and lack of cleavage. Commonly found in Brazil, Uruguay, Madagascar, and the United States (Arizona/North Carolina). Collectors should look for deep color saturation and crystal clarity.

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