mineral

Amethyst (Polished Point)

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 (Mohs scale); Color: Purple to violet; Luster: Vitreous; Crystal Structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple to violet
Luster: Vitreous

Identified June 27, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple to violet; Luster: Vitreous; Crystal Structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and basaltic geodes. The purple color is caused by gamma irradiation and trace amounts of iron taking the place of silicon in the crystal lattice. Most are of Cretaceous to Jurassic age.

Uses & applications

Primarily used for jewelry, lapidary art, and metaphysical collection. Large specimens are used as decorative home decor.

Geological facts

Amethyst is the birthstone for February. The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as ancient Greeks believed it could prevent drunkenness.

Field identification & locations

Identify by its purple hue and hexagonal (six-sided) crystal habit. In the field, look for volcanic geodes. Common locations include Brazil, Uruguay, and Zambia.

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