Folded Proterozoic gneiss, ColoradoApril 30, 2017/in /by Marli Miller igneous, metamorphic, Precambrian https://geologypics.com/wp-content/uploads/2017/04/geologic-time-pics-logo-300x115.png 0 0 Marli Miller https://geologypics.com/wp-content/uploads/2017/04/geologic-time-pics-logo-300x115.png Marli Miller2017-04-30 20:22:142017-11-06 07:20:58Folded Proterozoic gneiss, Colorado