mineral

Amethyst

Quartz (Silicon Dioxide) - SiO2 with Iron impurities

Hardness: 7 Mohs; Color: Light to dark purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 Mohs
Color: Light to dark purple
Luster: Vitreous (glassy)

Identified May 25, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Light to dark purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water cools. The purple color is caused by irradiation of iron impurities in the quartz structure over millions of years.

Uses & applications

Widely used for jewelry, lapidary arts, decorative home decor, and as a popular specimen for mineral collectors. Historically used for amulets and carvings.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as it was anciently believed to prevent drunkenness. It is the birthstone for February.

Field identification & locations

Identify by its distinct purple hue and crystal habit. Commonly found in Brazil, Uruguay, and Zambia. In the field, look for purple crystals inside host volcanic rock or rounded geodes.

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