mineral

Amethyst (Quartz)

Silicon Dioxide with Iron impurities (SiO2)

Hardness: 7 (Mohs scale); Color: Pale lilac to deep royal purple; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale lilac to deep royal purple
Luster: Vitreous (glassy)

Identified March 15, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale lilac to deep royal purple; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. Secondary mineralization occurs when silica-rich water fills cavities in volcanic rock, crystallizing over millions of years. Purple hue is caused by irradiation of iron impurities.

Uses & applications

Primary use is in jewelry, lapidary carvings, and as a decorative mineral specimen for collectors. Historically used in drinking vessels to 'prevent intoxication' and for spiritual or meditation purposes.

Geological facts

Amethyst was considered a Cardinal Gem (alongside Diamond and Ruby) until large deposits were found in Brazil in the 1700s, making it more common. It is the birthstone for February.

Field identification & locations

Identify by its distinct purple color, 6-sided crystal habit, and absence of cleavage. Found globally with major commercial deposits in Brazil, Uruguay, Zambia, and Ontario, Canada.

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