NameLayered Gneiss
TextureFoliated; Medium- to coarse-grained
CompositionQuartz, Feldspar, Biotite, and Hornblende
Index Minerals
ColorAlternating bands of white and black
MiscellaneousLayered or banded appearance
Metamorphic TypeRegional
Metamorphic GradeHigh Grade (High P - High T)
Parent RockShale, Mudstone, or Felsic Igneous rocks
Metamorphic EnvironmentHigh grade regional metamorphism along a convergent plate boundary

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