PURPOSE: To form a large pattern composed of granitelike particles by forming a pattern by bonding liquid dropletlike particles to the surface of a mold and subsequently charging a curable composition in the mold to cure the same.

CONSTITUTION: Sprayable coating prepared by compounding a filler, pigment or the like with a thermosetting resin is diluted with a solvent and sprayed to a lower mold 1a by a spray gun 4 to bond liquid droplet like particles 2 to the lower mold 1a. Next, sprayable coatings having different brightnesses, hues and color phases are successively sprayed to the surface of the lower mold 1a and an upper mold 1b and the lower mold 1a are registered to inject a composition prepared by compounding a filler and, if desired, pigment with a thermosetting resin in the molds. Subsequently, the composition is cured under heating and demolded to obtain a bathtub having a granitelike pattern and a beautiful smooth surface.