mineral

Amethyst (Faceted Gemstone)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple to Deep Violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Specific Gravity: 2.65

Identified February 21, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple to Deep Violet, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Specific Gravity: 2.65

Formation & geological history

Formed in geodes within igneous volcanic rocks such as basalts or rhyolites. Usually occurs through hydrothermal processes where silica-rich fluids deposit crystals in cavities over millions of years.

Uses & applications

Primarily used in jewelry (rings, necklaces), decoration, and metaphysical collections. Historically used as a gemstone of royalty.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as ancients believed it protected against drunkenness. It is the birthstone for February.

Field identification & locations

Identify in the field by searching for geodes in volcanic regions of Brazil, Uruguay, or Arizona. Look for purple geometric crystal points inside hollow volcanic rocks.

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