mineral

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Purple to violet with white quartz banding; Luster: Vitreous; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple to violet with white quartz banding
Luster: Vitreous

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple to violet with white quartz banding; Luster: Vitreous; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or volcanic geodes when silica-rich water deposits crystals inside cavities. The purple color is caused by irradiation of iron impurities within the quartz structure. Typical ages range from millions to hundreds of millions of years.

Uses & applications

Primarily used for semi-precious jewelry, ornamental carvings, spiritual/metaphysical practices, and as a popular collector's mineral.

Geological facts

Amethyst was considered a Cardinal Gem (one of the five most precious stones) until large deposits were found in Brazil in the 1700s. The name comes from the Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identified by its signature purple color, hexagonal crystal habits, and ability to scratch glass but not topaz. Commonly found in Brazil, Uruguay, and Africa. Collectors should look for deep color saturation and clarity.

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