To further improve the stability of a silver image by containing a metal having the electrode potential more positive than the electrode potential of silver in the electrochemical series at a specific quantity of metal ions for one liter in a finishing liquid.

A finishing liquid contains a metal having the electrode potential more positive than the electrode potential of silver in the electrochemical series at the quantity of 10-60 mg of metal ions for one liter, e.g. ions of gold, platinum, palladium, or iridium are used, and gold (III) ions and palladium ions are preferable in particular. Gold (III) ions of 10-30 mg for one liter is preferably used particularly under the existence of a wetting agent, e.g. the wetting agent of a nonyl phenol type. Thiocyanate ions at the total quantity of 50-500 mg/l, particularly 100-400 mg/l, are preferably used in a developer directly upstream of a fixing solution and/or in the fixing solution and/or in the finishing liquid.