Mineral

Amethyst

SiO2 (Silicon Dioxide)

Hardness: 7 on Mohs scale. Color: Violet to dark purple. Luster: Vitreous (glassy). Crystal Structure: Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Violet to dark purple
Luster: Vitreous (glassy)

Identified September 27, 2025More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Violet to dark purple. Luster: Vitreous (glassy). Crystal Structure: Hexagonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Formation & geological history

Amethyst typically forms in hydrothermal veins, pegmatites, and the cavities of volcanic rocks (geodes or vugs). The purple color is due to irradiation of iron impurities within the crystal lattice. Geological Age: Varies depending on formation location, can be found in rocks from various geological eras, including Precambrian to Cenozoic.

Uses & applications

Predominantly used as a gemstone in jewelry (rings, necklaces, earrings, bracelets). Also valued by collectors and for decorative purposes (geodes). Sometimes used in crystal healing practices.

Geological facts

Amethyst is the most valuable variety of quartz, after transparent rock crystal. Its name comes from the Ancient Greek 'amethystos', meaning 'not intoxicating', as it was believed to protect against drunkenness. Large deposits are found in Brazil and Uruguay.

Field identification & locations

Identify in the field by its characteristic purple color, hexagonal crystal shape (when found in geode linings), and hardness (it can scratch glass). Common locations include volcanic regions, particularly in Brazil, Uruguay, Bolivia, and parts of Africa (Zambia). Tips for collectors include looking for well-formed crystals within geodes or rock cavities.