mineral

Amethyst (Geode Fragment)

Silicon Dioxide with iron impurities (SiO2)

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple/Violet
Luster: Vitreous (glassy)

Identified June 14, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Purple/Violet; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: None; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) within igneous volcanic rocks. The purple color is caused by irradiation of trivalent iron impurities within the quartz structure.

Uses & applications

Primarily used in jewelry, lapidary arts, interior decoration, and as a popular specimen for mineral collectors.

Geological facts

Amethyst's name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness. It is the birthstone for February.

Field identification & locations

Identify by its characteristic purple color and hexagonal crystal points protruding from a base. Commonly found in Brazil, Uruguay, and Madagascar. In the field, look for volcanic basalt vugs or geodes containing crystalline structures.

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