Abstract: The invention relates to a casting core composition including refractory mullite grains and 1.0-2.2 wt % of a phenolic resin for binding the mullite grains. The mullite grains are substantially spherical in shape and have a special grain size distribution. That is, the mullite grains contain first to eighth fractions. These fractions respectively have first to eighth diameters which are respectively within ranges of larger than 420 .mu.m, 297-420 .mu.m 210-297 .mu.m, 149-210 .mu.m, 105-149 .mu.m, 74-105 .mu.m, 53-74 .mu.m, and smaller than 53 .mu.m.

Abstract: In a hatchback type motor vehicle having a hatchback door which is swingable relative to the vehicle body to open and close a door opening defined in the rear panel construction of the vehicle, there is proposed a rear lamp construction which comprises a first device mounted in the rear panel construction for producing light which is directed toward the door opening, and a second device mounted in the hatchback door for, when the door is in its closed position, reflecting the light coming from the first device toward the back of the vehicle.