mineral

Tumbled Amethyst

Quartz (Silicon Dioxide, SiO2)

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 1, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, purple to violet color, vitreous luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in hydrothermal veins and vugs in igneous and metamorphic rocks, often within basaltic gas cavities (geodes), through the crystallization of silica-rich solutions containing trace amounts of iron.

Uses & applications

Used primarily in jewelry, as a decorative gemstone, in ornamental carvings, and appreciated globally by crystal collectors.

Geological facts

Amethyst gets its distinctive purple color from irradiation acting on trace amounts of ferric iron impurities within the quartz crystal lattice.

Field identification & locations

Identified by its purple color and hardness (it easily scratches glass and cannot be scratched by a steel nail). Commonly found in Brazil, Uruguay, Zambia, and the United States.