Abstract: An apparatus is disclosed for horizontal direct chill casting of light metals, especially magnesium and magnesium alloys. The apparatus includes tundish for containing molten metal and a horizontally disposed mold in communication with the tundish. The mold has a primary cooling circuit for cooling mold walls such that the metal is chilled without any direct contact with the water. Also, a secondary direct cooling circuit is provided. The circuits for primary and secondary cooling water are independent of each other. An insulating transition ring is arranged at the mold entrance. It is important that the total mold depth is short, preferably between 25 and 45 mm. To obtain good surface quality and to avoid discoloring of the metal, it is preferred that the mold has an inlet for supplying protective gas to the transition ring. The inlet opening to the mold should be asymmetrically arranged, nearer the bottom of the mold.