It is demonstrated how by selection of pre-precursor cluster ions Ag 2 n + 1 2 + and collision-induced dissociation an ensemble of Ag 2 n 2 + can be produced, which is not contaminated by Ag n + clusters of the same size-to-charge state ratio, n/z. By use of this technique, Ag 1 6 2 + and Ag 1 8 2 + precursor ensembles have been prepared for further investigations. They are observed to decay by neutral monomer evaporation, Ag 2 n 2 + ->Ag 2 n - 1 2 + +Ag, and trimer fission, Ag 2 n 2 + ->Ag 2 n - 3 + +Ag 3 + , and show no sign of symmetric fission.