igneous
Quartz-rich granite or granitic pegmatite
Coarse crystalline aggregate of quartz (SiO₂), feldspar, and mica; exact identification is uncertain from the image
AI-generated identification · may be incorrectLight gray, rounded and weathered, with white translucent quartz/feldspar and dark mica or mafic minerals; crystalline texture and vitreous-to-pearly luster. Typical hardness is about 6–7 Mohs, with no obvious cleavage on the rounded surface.
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Physical properties
Light gray, rounded and weathered, with white translucent quartz/feldspar and dark mica or mafic minerals; crystalline texture and vitreous-to-pearly luster. Typical hardness is about 6–7 Mohs, with no obvious cleavage on the rounded surface.
Formation & geological history
Formed by slow cooling of silica-rich magma deep in the crust, producing interlocking crystals; commonly Precambrian to Phanerozoic in age. The rounded form likely reflects natural abrasion or deliberate tumbling.
Uses & applications
Granite is used for building stone, countertops, monuments, and aggregate; small attractive pieces are sold as landscaping or educational specimens rather than jewelry.
Geological facts
The pale mineral is probably quartz or feldspar, while the dark flakes may be biotite mica or hornblende. A fresh broken surface would reveal the diagnostic coarse “salt-and-pepper” texture.
Field identification & locations
Common in continental crust and granitic terrains worldwide; identify with a hand lens, glass-scratch test, and dilute acid test (no fizz expected). The image alone cannot distinguish granite confidently from related pegmatite or gneiss.
