mineral

Amethyst Cluster

Silicon Dioxide with Iron impurities (SiO2)

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Pale violet to deep purple
Luster: Vitreous (glassy)

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale violet to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and hollow cavities (geodes) within igneous volcanic rocks. The purple color is caused by irradiation of trivalent iron impurities. Most large deposits are found in basaltic rocks in Brazil and Uruguay.

Uses & applications

Used widely in jewelry, decorative carvings, and as a popular collector's mineral. Historically used as an amulet against intoxication.

Geological facts

Amethyst was considered one of the 'Cardinal Gems' along with diamond, ruby, sapphire, and emerald until large deposits were discovered in Brazil in the 19th century. Its name comes from the Greek word 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identifiable by its purple color and hexagonal prism crystal habits ending in 6-sided pyramids. Commonly found in basalt geodes. Collectors should look for deep, saturated color and crystal clarity.

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