The extent of copracipitation of copper with ferric hydroxide in the ammonium chloride-ammonia process has been studied. Pentavalent araenic and antimony may be present up to 10 mg, and phosphate, 50 mg. Aluminum exerts little effect. It is found that this mothod yields satisfactory results. The amount of copper coprecipitated in the ferric hydroxide precipitate is negligible in practical analysis.