mineral

Amethyst (Quartz Variety)

Amethyst (Silicon Dioxide - SiO2 with ferric iron impurities)

AI-generated identification · may be incorrect

Hardness: 7.0 on Mohs scale; Color: Pale lavender to deep violet/purple; Luster: Vitreous (glass-like); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7
Color: Pale lavender to deep violet/purple
Luster: Vitreous (glass-like)

Identified March 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins and cavities (geodes) of igneous rocks. The violet color results from irradiation, iron impurities, and the presence of trace elements. Major deposits date from various geological eras, notably the Cretaceous era in South America.

Uses & applications

Extensively used as a gemstone in jewelry (rings, necklaces), ornamental carvings, and widely collected by mineral enthusiasts for metaphysical or decorative display.

Geological facts

Ancient Greeks believed amethyst could prevent intoxication; the name comes from the Greek 'amethystos', meaning 'not drunk'. It is the birthstone for February and was once considered one of the five cardinal gemstones until large deposits were found in Brazil.

Field identification & locations

Identify by its characteristic purple terminal crystal points and hardness (cannot be scratched by a steel knife). Commonly found in Brazil, Uruguay, Zambia, and Canada. Look for rocky geodes or vugs in volcanic basalt regions.