igneous
Quartz–feldspar–mica rock, possibly pegmatite
Coarse-grained granitic rock (compositionally granitic pegmatite); exact identification requires closer examination
AI-generated identification · may be incorrectVisible coarse, interlocking pale quartz/feldspar and dark mica-like minerals; likely Mohs 6–7 overall, vitreous to pearly luster, crystalline texture, and feldspar cleavage. The photo does not establish exact mineral species or specific gravity.
Identified More igneous →
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Physical properties
Visible coarse, interlocking pale quartz/feldspar and dark mica-like minerals; likely Mohs 6–7 overall, vitreous to pearly luster, crystalline texture, and feldspar cleavage. The photo does not establish exact mineral species or specific gravity.
Formation & geological history
Likely crystallized slowly from silica-rich magma, allowing large crystals to grow; pegmatites commonly form late in the cooling of granitic intrusions, mostly during the Precambrian to recent geologic time.
Uses & applications
Comparable material is used as dimension stone, aggregate, and a source of feldspar, quartz, or mica; attractive pieces may be kept as specimens.
Geological facts
Pegmatites can contain exceptionally large crystals and rare minerals, though no distinctive rare mineral is evident here.
Field identification & locations
The coarse, contrasting grains suggest a granitic composition, but the specimen is weathered and the image is insufficient for a confident field identification. Granitic rocks and pegmatites occur worldwide, especially around continental intrusions.
