mineral

Amethyst (Rough Quartz)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Pale violet to deep purple (caused by irradiation and iron impurities); Luster: Vitreous/Glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Luster: Vitreous/Glassy

Identified April 7, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or inside geodic cavities (vugs) within volcanic rocks. The purple color is a result of natural irradiation of trace iron during the crystallization process. Ages can span from millions to hundreds of millions of years Depending on the host formation.

Uses & applications

Primarily used in jewelry (faceting), decorative ornaments, and as a popular specimen for mineral collectors and metaphysical practitioners.

Geological facts

Amethyst was considered a 'Precious Stone' alongside Diamond, Ruby, Sapphire, and Emerald until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its purple hue, lack of cleavage, and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for hexagonal crystal points or conchoidal (shell-like) fractures in rough pieces.

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