mineral

Amethyst (Chevron or Banded variety)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale), Color: Purple with white/gray quartz banding, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Identified March 23, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Purple with white/gray quartz banding, Luster: Vitreous (glassy), Crystal Structure: Trigonal/Hexagonal, Cleavage: None (Conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or volcanic cavities (geodes). The purple color is caused by gamma irradiation of trace iron minerals within the quartz lattice. The chevron pattern occurs when amethyst and white quartz grow in alternating layers.

Uses & applications

Used primarily as a semi-precious gemstone in jewelry, for decorative carvings, as 'healing stones' in metaphysical practices, and as mineral specimens for collectors.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' and was as valuable as diamonds until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not intoxicated', due to a belief that the stone prevented drunkenness.

Field identification & locations

Identify by its distinct purple color and V-shaped (chevron) or straight white quartz banding. Often found as tumbled stones or in geodes. Prime locations include Brazil, Uruguay, Namibia, and Arizona, USA.

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