mineral

Amethyst Cluster

Silicon Dioxide (SiO2) with iron impurities

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 3, 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 or volcanic geodes when silica-rich water cools. The purple color is caused by trace amounts of iron and natural irradiation in the surrounding rock. Ages vary from 100 million to over 1 billion years old.

Uses & applications

Predominantly used for jewelry, lapidary art, and as a popular collector's mineral specimen. Historically used in glassware and amulets.

Geological facts

Amethyst was considered a Cardinal Gem until the 18th century, as precious as diamond or ruby, until large deposits were found in Brazil. The name comes from the Greek 'amethystos', meaning 'not drunken', as it was believed to prevent intoxication.

Field identification & locations

Identify by the iconic purple hue and six-sided prismatic crystals. Found mostly in Brazil, Uruguay, and Africa. Collectors should look for deep, uniform color (Siberian color) and large crystal points with minimal damage.

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