mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on the Mohs scale; Color: light lilac to deep intense purple; Luster: Vitreous/glassy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: light lilac to deep intense purple
Luster: Vitreous/glassy

Identified January 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous rocks. The purple color is caused by irradiation of iron impurities within the quartz lattice. Ages vary depending on the host rock, often millions of years old.

Uses & applications

Primarily used in jewelry (as faceted stones or beads), decorative carvings, and as a popular specimen for mineral collectors. Historically preferred as a semi-precious gemstone.

Geological facts

In Greek, 'amethystos' means 'not drunken'; ancient Greeks wore it to protect against intoxication. It is the birthstone for February and was once considered one of the 'Cardinal Gems' along with diamonds and rubies.

Field identification & locations

Identify in the field by its distinct purple color, hexagonal crystal habit (six-sided prisms), and lack of cleavage. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Collectors should look for its transparency and deep saturation of color.

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