igneous
Coarse-grained granite or granitic gneiss
Granite; primarily quartz, feldspar, and mica (possibly foliated into gneiss)
AI-generated identification · may be incorrectLight gray, speckled, and coarse crystalline with visible quartz and feldspar; mica produces dark reflective flakes. Hardness is about 6–7 Mohs, with no obvious cleavage as a whole rock and a granular crystal texture.
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Physical properties
Light gray, speckled, and coarse crystalline with visible quartz and feldspar; mica produces dark reflective flakes. Hardness is about 6–7 Mohs, with no obvious cleavage as a whole rock and a granular crystal texture.
Formation & geological history
Likely formed by slow cooling of silica-rich magma deep in the crust, commonly during Precambrian to Phanerozoic mountain-building events; any banding or alignment would indicate later metamorphism to gneiss.
Uses & applications
Widely used as dimension stone, countertops, monuments, paving, aggregate, and architectural material; attractive hand specimens have modest collecting value.
Geological facts
Granite’s interlocking crystals reflect slow underground cooling. The specimen’s subtle mineral alignment and irregular dark seams may indicate granitic gneiss rather than unaltered granite.
Field identification & locations
Identify it by coarse interlocking quartz, white or pink feldspar, and black mica; unlike basalt, it is pale and visibly crystalline. Common worldwide in continental crust and exposed mountain ranges.
