This work presents the processing and the characterization of diopside-Ca-Tschermak clinopyroxene-based glass-ceramics (GCs), where partial (i.e., 5%, 10%, and 20%) substitution of Ba for Ca was attempted in the composition of CaMg0.8Al0.4Si1.8O6. Sintering, crystallization, microstructure, and properties of the new materials were investigated under different heat-treatment conditions concerning heating rates (5-40 K/min), temperatures (850 degrees-1000 degrees C), and times (1-300 h). The good matching of thermal expansion coefficients and the strong, but not reactive, adhesion to yttria-stabilized cubic zirconia, in conjunction with the low level of electrical conductivity and oxygen permeability, indicate that the investigated GCs are suitable for further experimentation as candidates for solid oxide fuel cells sealants.