Metamorphic microstructures include textures formed by the development of [[foliation (geology)|foliation]] and overprinting of foliations causing [[crenulation]]s.
On the thin section and hand specimen scale a metamorphic rock may manifest a planar penetrative fabric called a [[foliation (geology)|foliation]] or a [[cleavage (geology)|cleavage]]. Several foliations may be present in a rock, giving rise to a [[crenulation]].