mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Hardness: 7 (Mohs scale); Color: Purple to pale violet; Luster: Vitreous; Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

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

Identified June 6, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple to pale violet; Luster: Vitreous; Crystal structure: Trigonal; Cleavage: None; Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks when silica-rich water cools. The purple color comes from iron irradiation during formation.

Uses & applications

Primarily used in jewelry, as decorative collector specimens, and in spiritual/metaphysical practices.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones along with diamond, ruby, sapphire, and emerald. Large deposits in Brazil made it more common.

Field identification & locations

Identify by its purple hue and hexagonal crystal faces. Commonly found in Brazil, Uruguay, Zambia, and South Korea. Look for its transparency and 6-sided points in the field.