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Orthogneiss
Ptygmatic folds in gneiss
Orthogneiss
Paragneiss
 
Greenschist-grade meta-basalt
Andalusite porphyroblasts
Orthogneiss
Magnetite-apatite-actinolite replacing albitized metasediments
 
Magnetite-apatite-actinolite replacing albitized metasediments
Contact metamorphosed concretions
Acasta gneiss - world's oldest rocks - 4.0 Ga
Acasta gneiss - world's oldest rocks - 4.0 Ga