Friction versus load plot for experiment Cd-1 and related height/fricion images. a) The friction vs. load plot shows that at low loads the calcite contact possess a slightly higher friction than that calculated for a single layer of calcian otavite, but at higher loads, the friction force is larger on the calcian otavite film. b) Height/friction image corresponding to a load of 14 nN. White lines on the height image represent the original calcite steps prior to the start of the calcian otavite film growth. c) Height/friction images corresponding to a load of 40 nN. d) Height/friction images corresponding to a load of 72 nN.