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Compositionally related glasses and ceramics of the Na$ sb2$O$ cdot$CaO$ cdot$Al$ sb2$O$ sb3 cdot$TiO$ sb2 cdot$SiO$ sb2$ system (sphene glass-ceramics) doped with Eu$ sp{3+}$ were examined using site-selective spectroscopic techniques (FLN). In sphene glass-ceramics, Eu$ sp{3+}$ preferentially partitions into the crystalline sphene phase. The partition ratio is concentration dependent, decreasing at higher concentrations, because of the limited solid solubility of Eu$ sp{3+}$ in sphene. The concentration occurs at the time of phase separation; Eu$ sp{3+}$ preferentially enters the more ionic (CaO, TiO$ sb2$)- rich droplet phase which eventually becomes sphene. In sphene, Eu$ sp{3+}$ substitutes for Ca$ sp{2+}$ appearing in three different sites caused by associated charge compensation defects. From an analysis of the FLN spectra of the different glasses, the framework for a model describing the coordination shell of Eu$ sp{3+}$ in oxide glasses is developed. The model suggests that Eu$ sp{3+}$ behaves as a network forming ion or quasi-molecular complex. The model is used to explain qualitative features of Eu$ sp{3+}$ FLN spectra including the dependence of the clustering of points of the major crystal field parameter ratios plot on the relative number of non-bridging oxygen ions and Eu$ sp{3+}$ ions in the glass.