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Techniques and results are given for the floating zone refining of Ni, Ti, V, and for boat zone refining of A1 and Au. These elements have been purified by zone melting. A considerable amount of purification was obtained by volatil ization during floating zone melting. The need for purer metals for basic research and deve lopment purposes is great. Because of these needs, we have zone refined a number of metals by f loating zone and boat techniques. Some of the results are discussed here. Floating Zone Refining Equipment The floating zone ref ining was done in vacuum in a vapor p lat ing unit I adapted for this work. It is s iml i lar to the unit used by Buehler (1). F igure 1 shows a schematic drawing of the equipment. The l iquid n i t rogen trap, diffusion, and mechanica l pumps are not shown. The ends of the rod to be zone refined are placed in quartz holders which in turn are held i