<p>A metal halide lamp comprises a luminous tube alone without any outer bulb, the luminous tube containing metal halides such as neodymium halides (NdX3), dysprosium halides (DyX3) and cesium halides (CsX) in a total amount by mole of 1 x 10<-><6> to 8 x 10<-><6> mol/cc and the following molar ratios: <MATH> as well as argon serving as starting auxiliary gas and mercury serving as buffer gas. This structure permits a predetermind vapour pressure of the metal halides sealed in the luminous tube to be obtained without increasing the wall load, as well as the formation of a metal halide lamp having a long life and good colour characteristics.</p>
