A thermally stable chalcogenide glass, a process for making the same, and an optical fiber drawn therefrom are provided. A chalcogenide glass having the composition Ge(5−y)As(32−x)Se(59+x)Te(4+y) (0≦y≦1 and 0≦x≦2) is substantially free from crystallization when it is heated past the glass transition temperature Tg or drawn into optical fibers. A process for making the thermally stable chalcogenide glass includes purifying the components to remove oxides and scattering centers, batching the components in a preprocessed distillation ampoule, gettering oxygen impurities from the mixture, and heating the components to form a glass melt. An optical fiber formed from the chalcogenide glass is substantially free from crystallization and exhibits low signal loss in the near-infrared region, particularly at wavelengths of about 1.55 μm.