mineral
Amethyst cluster
Amethyst, purple quartz (SiO₂)
AI-generated identification · may be incorrectMohs hardness 7; purple to lilac color with a vitreous luster and trigonal crystal structure. Quartz has no true cleavage and commonly breaks with conchoidal fracture.
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Physical properties
Mohs hardness 7; purple to lilac color with a vitreous luster and trigonal crystal structure. Quartz has no true cleavage and commonly breaks with conchoidal fracture.
Formation & geological history
Forms when silica-rich fluids deposit quartz crystals in cavities, often in volcanic rocks. The exact age and locality cannot be determined from the image.
Uses & applications
Used in jewelry, decorative objects, and mineral collections.
Geological facts
Amethyst’s color comes mainly from trace iron and natural irradiation; heating can turn some amethyst yellow or orange.
Field identification & locations
Identify by its purple, glassy quartz crystals, typically with pointed terminations; common sources include Brazil, Uruguay, and Zambia. The specimen appears to be a small rough cluster.
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