mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Hardness: 7 (Mohs scale); Color: Pale lilac to deep purple; Luster: Vitreous (glass-like); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale lilac to deep purple
Luster: Vitreous (glass-like)

Identified March 15, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale lilac to deep purple; Luster: Vitreous (glass-like); Crystal structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings inside volcanic geodes. The purple color is caused by irradiation of trivalent iron (Fe3+) within the quartz structure. They are found across various geological ages, often in basaltic rocks.

Uses & applications

Predominantly used as a gemstone in jewelry (rings, necklaces, carvings), as decorative specimens for collectors, and in spiritual/healing practices.

Geological facts

Until the 18th century, amethyst was included in the cardinal gemstones alongside diamond, ruby, emerald, and sapphire. It is the birthstone for February and was believed by ancient Greeks to prevent intoxication.

Field identification & locations

Identify in the field by its distinct purple color, lack of cleavage, and ability to scratch glass. Commonly found in Brazil, Uruguay, Zambia, and Russia. Collectors should look for intense color saturation and clarity.

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