mineral

Amethyst (Polished Cabochon)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7.0 Mohs; Color: Purple/Violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

Hardness: 7
Color: Purple/Violet
Luster: Vitreous (glassy)

Identified April 21, 2026More mineral →

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Physical properties

Hardness: 7.0 Mohs; Color: Purple/Violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and geodes, typically appearing in those within volcanic rocks. The purple color is caused by irradiation of iron impurities within the quartz lattice.

Uses & applications

Primarily used in jewelry (as shown in the cabochon cut), ornamental objects, and as a popular specimen for mineral collectors.

Geological facts

Amethyst is the birthstone for February. In ancient times, the Greeks believed wearing it would prevent intoxication; the name comes from 'amethystos,' meaning 'not drunk.'

Field identification & locations

Identify by its distinct purple hue and 7.0 hardness (it will scratch glass). While common worldwide, major high-quality deposits are found in Brazil, Uruguay, and Zambia.

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