In this paper we report on optical and spectroscopic properties of an innovative erbium-doped modified silicate Baccarat glass of molar composition: 77.29SiO 2 :11.86K 2 O:10.37PbO:0.48Sb 2 O 3 . Two different sets of samples were produced, containing 0.2 and 0.5 mol% Er 3+ ions, respectively. Optical and spectroscopic assessment of these glasses was performed by absorption, photolumines-cence, and refractive index measurements. The quantum efficiency was estimated comparing measured and radiative lifetime of the 4 I 13/2 metastable state of the Er 3+ , the latter obtained by Judd–Ofelt analysis.