Abstract: We present novel experimental results about influences of surrounding foreign materials on optical properties of small silver clusters. First we show spectra of free cluster beams produced with different seeding gases Ar, Kr, Xe. Second, we estimate, from measured spectra, the cluster deformations and contact areas after deposition on different substrates (Cr2O3 and MgF2) at room temperature and on SiO2 at 110 K and between 160 K and 300 K. Third, we present and compare the static and dynamic charge transfer after embedding the clusters in various fluorides and compare with previous results on oxides.