Answer:
Foliation is a strong, parallel alignment of coarse mica flakes and/or of different mineral bands in a metamorphic rock.
Explanation:
Foliation is most commonly prevalent in metamorphic rocks. Foliation is the parallel alignment of textural and structural features of a rock.
Differential stress plays a major role on the texture of metamorphic rocks because it forces the mineral constituent of the rocks to align parallel to each other. Foliation can occur in different ways for example a mineral like mica which is usually platy can crystallize in rocks , due to differential stress the mineral grows in such a way it remains parallel to the movement in which the part of the rock slide relative to one another and parallel to the forces applied or the mineral might grow perpendicular to the direction of the compressed stress.
Notice the foliation in the texture of gneiss .You can see the light and dark mineral found in separate or parallel layer.
