mineral
Polished smoky quartz pebble (probable)
Quartz, SiO₂; smoky coloration is caused by trace aluminum and natural irradiation
AI-generated identification · may be incorrectTranslucent brown-gray with a glassy polish; quartz has Mohs hardness 7, a trigonal crystal structure, no cleavage, and conchoidal fracture. The visible inclusions and limited view make identification provisional.
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Physical properties
Translucent brown-gray with a glassy polish; quartz has Mohs hardness 7, a trigonal crystal structure, no cleavage, and conchoidal fracture. The visible inclusions and limited view make identification provisional.
Formation & geological history
Quartz crystallizes from silica-rich fluids in veins and pegmatites; smoky color develops through irradiation of trace impurities. Its geological age depends on the host deposit and cannot be determined from the image.
Uses & applications
Small polished quartz pieces are used in jewelry, craftwork, and mineral collections.
Geological facts
Quartz is one of Earth’s most abundant minerals; polishing can make inclusions and color zoning easier to see.
Field identification & locations
A glassy luster and hardness near 7 support quartz identification; a scratch test on an inconspicuous spot can help distinguish it from softer lookalikes. Quartz occurs worldwide in igneous, metamorphic, and sedimentary settings.
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