The meaning of a scalar crystal field strength parameter defined previously [4, 5] is studied. It is shown why, in many cases, it can be used as an indication of the magnitude of the maximum Stark splitting of J-terms for ions in crystals of different structures and site symmetries. It thus provides a way of making use of the existing tables of Bkq parameters for comparing crystals of different symmetries and for predicting the relative magnitude of their Stark splittings. Reciprocally, maximum Stark splittings provide a simple mean of comparing crystal field strengths of different crystals