In this work possibilities for improving the luminescence properties of rare-earth(RE)-doped fluorochlorozirconate(FCZ) glass ceramics are explored for their photovoltaic, laser and medical applications. The focus of this study lies on analyzing the positive effect of BaCl2 nanocrystals in the glass on the RE-luminescence. For this purpose, the excitation and relaxation dynamics of the RE-ion Nd3+ is investigated using time-resolved laser spectroscopy. In particular, the multiphononrelaxation (MPR) rates of individual Nd3+ levels are determined. Temperature-dependent investigations show that interactions of the RE-ions with phonons of the BaCl2-nanocrystals lead to extremely low MPR-rates and thus result in strongly improved quantum efficiencies. Furthermore, a Mössbauer spectroscopy study of Eu-doped FCZ glass ceramics is carried out in order to point out routes for determining and optimizing the RE oxidation state.