mineral

Amethyst (Geode)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Violet to deep purple; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Violet to deep purple
Luster: Vitreous

Identified April 11, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Violet to deep purple; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks, often through the accumulation of silica-rich fluids after volcanic activity. Many specimens date from the Cretaceous period.

Uses & applications

Used extensively in jewelry (as a gemstone), ornamental carving, and as a popular decorative high-energy specimen for collectors and metaphysical practitioners.

Geological facts

Amethyst was considered a precious stone similar to Ruby and Emerald until the discovery of large deposits in Brazil in the 19th century. Its name comes from the Greek 'amethystos,' meaning 'not intoxicated.'

Field identification & locations

Identify by its purple color, crystal habit (six-sided prisms), and hardness. Commonly found in Brazil, Uruguay, and Zambia. In the field, look for chalcedony geodes with crystalline interiors.

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