Precursors of Cu/ZnO catalysts with various Cu/Zn molar ratios were prepared by a coprecipitation method. It was found that amorphous copper hydroxycarbonate and sodium zinc carbonate were intermediates for the formation of various precursors such as hydrozincite, malachite and aurichalcite. Aurichalcite having a high Cu/Zn ratio was prepared from a mechanical mixture of these intermediates.