The Hungarian chemist George Charles de Hevesy (1885-1966) was a pioneer of isotope labeling and codiscoverer of the element hafnium.

George de Hevesy was born in Budapest on Aug. 1, 1885. He studied at Freiburg, Zurich, and Karlsruhe and in 1911 joined Ernest Rutherford at Manchester. His assignment there, to separate radium-D from lead, proved impossible, because radium-D, as was later demonstrated, actually comprises isotopes. Yet the 2 years were not wasted, for Hevesy gained valuable technical experience in the new field of radiochemistry. In 1913 he left for Vienna to join F. A. Paneth, whose experience with radium-D had been similar. They studied the exchange between radioactive and nonradioactive lead atoms, showing that, for all ordinary processes, the chemical and physical behavior of these atoms was identical. Also, by using radioactive (labeled) samples to determine the solubilities of various lead salts, they introduced the technique of radioactive tracers.

In 1920 Hevesy moved to...