igneous
Small gray rock fragment, likely granite or diorite
Uncertain; probable coarse-grained silicate rock dominated by feldspar and quartz, possibly biotite/hornblende
AI-generated identification · may be incorrectHardness about 6–7 Mohs; gray, uneven granular texture with dull to weakly vitreous luster. Interlocking crystalline grains and no obvious cleavage at this scale; density likely around 2.6–2.8 g/cm³.
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Physical properties
Hardness about 6–7 Mohs; gray, uneven granular texture with dull to weakly vitreous luster. Interlocking crystalline grains and no obvious cleavage at this scale; density likely around 2.6–2.8 g/cm³.
Formation & geological history
Likely an intrusive igneous fragment that crystallized slowly from magma deep underground, commonly during Precambrian or Phanerozoic continental crust formation. The image alone cannot establish its exact age or composition.
Uses & applications
Granite and diorite are widely used as building stone, aggregate, monuments, countertops, and paving; this small fragment has negligible commercial value.
Geological facts
The specimen appears naturally fractured and may be granite, diorite, or another granitic rock. A fresh surface, hand lens, streak test, and acid test would improve identification.
Field identification & locations
Look for visible interlocking feldspar, quartz, and dark mineral grains; granite is generally lighter and quartz-rich, while diorite is darker and quartz-poor. Common worldwide in continental plutons and exposed mountain ranges.
