This paper summarizes the results of experiments on the precipitation of zinc by slow decomposition of ethyl oxalate. With slight modification, the procedure for the precipitation of magnesium is also suitable for zinc. If used without modification, the zinc oxalate is precipitated in very large crystals that are not only inconvenient to filter but apparently impure. Such crystals are formed when the precipitation from homogeneous solutions occurs at too slow a rate. By using more ethyl oxalate initially the rate is increased, crystals of desirable physical properties and purity are obtained, and the time of precipitation is shortened.