mineral

Amethyst (Quartz)

Amethyst (Silicon Dioxide with Iron impurities, SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Pale lavender to deep purple
Luster: Vitreous (glassy)

Identified April 4, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Pale lavender to deep purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or as linings within geodes inside igneous rocks. The purple color comes from irradiation of iron impurities within the quartz crystal structure.

Uses & applications

Primarily used in jewelry (as a semi-precious gemstone), decorative carvings, and as a popular specimen for mineral collectors.

Geological facts

Amethyst was once considered one of the 'Cardinal gems' (alongside diamond, ruby, sapphire, and emerald) until large deposits were found in Brazil. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', due to a belief it protected its owner from drunkenness.

Field identification & locations

Identify in the field by its purple hue, hexagonal crystal points, and inability to be scratched by a steel knife. Commonly found in Brazil, Uruguay, Zambia, and Ontario, Canada.