Abstract: A refractive block of ceramic material as a burner block or the like for furnace walls, is provided with a surrounding rib with recesses. A frame of suitably rigid and refractive angle bars encompasses the block and receives bolts extending transversely through the recesses and into or through the furnace wall. The bolts are anchored in both the frame and furnace wall and bear against the block inner face for securing the block in position, avoiding the danger of spawling or breaking out the block.