mineral

Amethyst

Amethyst (Silicon Dioxide with iron impurities), SiO2

Hardness: 7 on Mohs scale; Color: Pale lavender to deep violet; Luster: Vitreous (glassy); Crystal structure: Trigonal (Hexagonal system); Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

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

Identified March 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lavender to deep violet; Luster: Vitreous (glassy); Crystal structure: Trigonal (Hexagonal system); Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or cavities (geodes) within igneous rocks, typically basalt. The purple color is caused by irradiation of iron impurities within the quartz structure. Most specimens vary in age based on host rock, frequently Cretaceous to Paleogene.

Uses & applications

Commonly used in jewelry (faceting and cabochons), metaphysical practice, and as ornamental mineral specimens for collectors.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to protect its owner from drunkenness.

Field identification & locations

Identify by its characteristic purple color, hardness (will scratch glass), and lack of cleavage. Commonly found in Brazil, Uruguay, Zambia, and Canada. Look for hexagonal crystal terminations in geodes in the field.

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