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An europium doped BaO–B₂O₃–BaCl₂ chloroborate glass-ceramic containing a BaCl₂ nanocrystalline phase was produced by melt-quenching followed by glass crystallization during annealing. Structural and morphological investigations using x-ray diffraction and scanning electron microscopy have shown fvBaCl₂ nanocrystals of about tens of nm size accompanied by a smaller amount of the BaB₂O₄ crystalline phase. Photoluminescence spectra have indicated the reduction of Eu³⁺ to Eu²⁺ during processing in air or a reducing atmosphere. The spectra analysis showed the presence of Eu³⁺ ions in the borate glass matrix, while the Eu²⁺ were incorporated in both the BaCl₂ nanocrystals and glass matrix. Thermoluminescence properties were due to the recombination of F(Cl) centers and Eu²⁺ related hole centers produced by irradiation within the BaCl₂ nanocrystals. The color impression of the samples and the photoluminescence quantum efficiency were influenced by the glass processing.