mineral

Amethyst (Chevron Amethyst)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Purple with white/clear quartz bands; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple with white/clear quartz bands
Luster: Vitreous (glassy)

Identified June 19, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple with white/clear quartz bands; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or volcanic geodes when silicon dioxide-rich fluids crystallize. The purple color is caused by irradiation and iron impurities. This banded variety often indicates fluctuating growth conditions.

Uses & applications

Used primarily in jewelry, lapidary arts (cabochons, beads), and as a popular decorative or metaphysical gemstone for collectors.

Geological facts

Amethyst was considered a cardinal gem until the 18th century, valued as highly as diamonds until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its distinctive purple hue and lack of cleavage (conchoidal fracture). It will scratch glass but cannot be scratched by a steel knife. Commonly found in Brazil, Uruguay, and Namibia.

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Metamorphic Rock

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