mineral

Amethyst (Rough Crystal)

Silicon Dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 7 Mohs; Color: Light to deep purple/violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None; SG: 2.65

Hardness: 7 Mohs
Color: Light to deep purple/violet
Luster: Vitreous

Identified July 14, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Light to deep purple/violet; Luster: Vitreous; Crystal Structure: Hexagonal (trigonal); Cleavage: None; SG: 2.65

Formation & geological history

Forms in hydrothermal veins or volcanic geodes when silicon dioxide and trace amounts of iron are irradiated by natural gamma radiation from surrounding rocks. Commonly found in basaltic rocks.

Uses & applications

Primarily used in jewelry, as decorative display specimens, and in alternative healing practices (crystal healing). Larger specimens are used in industrial lapidary.

Geological facts

Amethyst was considered as valuable as diamonds until large deposits were found in Brazil in the 1700s. Its name comes from the Greek 'amethystos', meaning 'not intoxicated'.

Field identification & locations

Identify by its characteristic purple hue and hexagonal crystal habit. Common locations include Brazil, Uruguay, Zambia, and Ontario. Collectors look for clarity and deep saturation.