mineral
Amethyst crystal
Amethyst, purple variety of quartz (SiO₂), trigonal crystal system
AI-generated identification · may be incorrectHardness 7 on the Mohs scale; typically purple with vitreous luster and no true cleavage, breaking with conchoidal fracture. The specimen appears to be a naturally formed, possibly cut or polished purple quartz crystal.
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Physical properties
Hardness 7 on the Mohs scale; typically purple with vitreous luster and no true cleavage, breaking with conchoidal fracture. The specimen appears to be a naturally formed, possibly cut or polished purple quartz crystal.
Formation & geological history
Forms when iron-bearing quartz is exposed to natural irradiation, commonly lining cavities in volcanic rocks. Amethyst deposits span a wide range of geological ages; the image alone cannot determine this specimen’s age or locality.
Uses & applications
Used in jewelry, carvings, and mineral collections; lower-grade material is also used for ornaments and polished objects.
Geological facts
Amethyst’s purple color is associated with trace iron and irradiation; heating can turn some amethyst yellow or orange, producing citrine-like material.
Field identification & locations
Identify by its purple color, glassy luster, hardness, and quartz-like fracture; major sources include Brazil, Uruguay, Zambia, and Madagascar. The image does not establish whether it is natural, treated, or mounted.
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