mineral

Amethyst (Quartz)

Silicon Dioxide (SiO2) with Iron impurities

Hardness: 7 on Mohs scale. Color: Pale violet to deep purple. Luster: Vitreous (glassy). Crystal structure: Trigonal/Hexagonal. Cleavage: Indistinct. Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Pale violet to deep purple
Luster: Vitreous (glassy)

Identified May 17, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Pale violet to deep purple. Luster: Vitreous (glassy). Crystal structure: Trigonal/Hexagonal. Cleavage: Indistinct. Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) when silica-rich solutions precipitate. The purple color is caused by gamma irradiation of trivalent iron impurities. Found in volcanic rocks like basalt or metamorphic host rocks.

Uses & applications

Primarily used in jewelry (faceting, cabochons), carvings, as decorative healing crystals, and as a popular specimen for mineral collectors.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' alongside diamond, sapphire, ruby, and emerald until large deposits were found in Brazil, making it more common. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identified by its purple hue and hexagonal crystal faces. Commonly found in Brazil, Uruguay, and parts of North America. Collectors look for deep saturation and clarity. Exposure to high heat or sun can cause the color to fade.

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