Biological Elements

At the beginning of the "Biochemistry of the Lanthanides" (Plenum, NY, 1990), I made some remarks concerning the history of the rare earth elements and commented that there was "enough material here for an historian of science to write an instructive book on the identification of the lanthanides in its own right". Little did I think when writing these words that just a few years later I would be editing such a volume which, in recognition of the growing industrial, biological and medical importance of these elements, has been extended to include a second section, devoted to their application.