Ceramic metal halide lamp

A metal halide lamp (10) includes a discharge vessel (12) which may be formed of a ceramic material. The vessel defines an interior space (16). An ionizable fill is disposed in the interior space. The ionizable fill includes an inert gas and a halide component. The halide component includes a sodium halide, a cerium halide, at least one of a thallium halide and an indium halide, and optionally a cesium halide. The cerium halide is at least about 9 mol% of the halide component. At least one electrode (18, 20) is positioned within the discharge vessel so as to energize the fill when an electriccurrent is applied thereto.