MkIIGB divertor tiles exposed in JET for the 1998-2001 and 1999-2001 campaigns have been used to assess the amount of beryllium and carbon deposited at the inner divertor wall. Deposited lms at the inner wall of the divertor tiles have a duplex nature. There is an inner layer rich in carbon and beryllium, whereas the outer layer is rich in deuterium and carbon. Total amount of beryllium at the inner divertor tiles was determined and integrated toroidally. Results were compared with spectroscopic data and good agreement was obtained. The amount of carbon was computed assuming that the ratio of carbon to beryllium arriving in the divertor is the same as the observed source ratio in the main chamber. On the basis of this analysis we would expect there to be ~0.4kg of carbon deposited. This gives an average carbon deposition rate lower than during the MkIIA phase.