mineral

Tumbled Amethyst

Silicon Dioxide (SiO2) with iron impurities

Hardness: 7 on Mohs scale. Color: Deep purple to pale violet. Luster: Vitreous to waxy (when polished). Crystal structure: Hexagonal/Trigonal. Cleavage: None (conchoidal fracture). Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Deep purple to pale violet
Luster: Vitreous to waxy (when polished)

Identified July 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed in geothermal environments, igneous rock cavities (geodes), and hydrothermal veins when silica-rich fluids cool and crystallize in the presence of trace ferric iron (Fe3+) and natural irradiation.

Uses & applications

Popular for lapidary work, jewelry, tumbled stone collections, decorative carvings, and metaphysical practices.

Geological facts

Amethyst gets its purple coloration from trace amounts of iron substituted into the quartz crystal lattice combined with natural gamma radiation. Heating amethyst can turn it yellow or orange, converting it into heat-treated citrine.

Field identification & locations

Identify by its hardness (scratches glass), glass-like luster, and distinct purple color zoning. Major sources include Brazil, Uruguay, Madagascar, Zambia, and Russia. Very common and easily acquired by beginner collectors.

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