Optical Identification of Few-Layer Graphene Obtained by Friction
  A friction based method is proposed for obtaining graphite layers. Freestanding thin structures of graphite containing several layers of graphene are obtained by rubbing a graphite rod on the surfaces of NaCl substrate and then dissolving the substrate in water. An optically transparent and mechanically strong lamina of few-layer graphene is found in the obtained structures. 
Manuel Mailian, Kamran ul Hasan, Aram Mailian
cond-mat.mtrl-sci