PURPOSE: To finish the surface of a blank material like natural stone having various shapes by a simple method by press sticking and fixing inorg. granules on the surface of the blank metallic material.

CONSTITUTION: Granules 2 of black and other colors are blown by a shot blasting method or the like using compressed air onto a blank material 1 made of Al or the like annealed after drawing so that the granules are gnawed into the surface 1a of the blank material. While part of the granules 2 are held projected from the surface 1a, the granules are press-stuck and fixed to form recesses 4 on the surface 1a. The recessed parts 4 provide a matting effect on the surface 1a of the material 1. The recessed part reflect rays according to the incident directions thereof, thus providing the surface 1a like natural stone. Alternately, the inorg. granules 2 are seated on the surface of the metallic blank material such as a plate or the like and the material is passed between rolls or the like to press-stick and fix the granules 2. According to such method, the metallic material suited for materials for buildings such as columns of gates is obtained by working in a short time.