mineral

Amethyst Quartz (Tumbled)

Amethyst (Silicon Dioxide with iron impurities, SiO2)

Hardness: 7.0 on Mohs scale; Color: Pale lavender to deep violet/purple; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7
Color: Pale lavender to deep violet/purple
Luster: Vitreous (glassy)

Identified March 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins or as linings within volcanic rock geodes (vugs). The purple color is caused by natural irradiation of trace amounts of iron within the crystal lattice. Geological age varies greatly but most commercial specimens are from the Cretaceous period.

Uses & applications

Primarily used as a gemstone in jewelry (rings, necklaces), for lapidary work (cabochons, tumbles), and as decorative display specimens. Also used in spiritual or metaphysical practices.

Geological facts

Amethyst was once considered one of the 'Cardinal Gems' along with diamond, ruby, emerald, and sapphire until large deposits were found in Brazil. Its name comes from the Ancient Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness.

Field identification & locations

Identify in the field by its purple hue and hexagonal crystal shape if not tumbled. It is typically found in Brazil, Uruguay, and South Korea. Collectors should look for deep uniform color and high transparency.

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