A secondary cooling apparatus capable of gradually cooling cast thin pieces and a cast apparatus that uses it are provided. A comb tooth-shaped device is arranged inside a vessel of the secondary cooling apparatus; the cast thin pieces are piled on the comb tooth-shaped device; and crushed small pieces are placed thereon. After the cast thin pieces and the crushed small pieces are gradually cooled, the cast thin pieces are crushed by a pressing device. The crushed small pieces are rapidly cooled by being in contact with a surface of a bottom wall and side faces of cooling teeth. Nd-rich phases or R-rich phases can be annealed by the gradual cooling, and after the crushed small pieces are rapidly cooled to its oxidation temperature or below, the crushed small pieces can be taken out to the air atmosphere.