Typical modern histories of the discovery of the chemical elements report that element 43 was discovered in Italy in 1937 by Perrier and Segre. According to these accounts, the discovery was made by chemical separation in a sample of deuteron-bombarded molybdenum, supplied by E. Lawrence, and thus represent the first discovery of an element produced artificially and is the reason for the name “technetium” (Tc) chosen by the investigators. Some accounts might note in passing that the existence of element 43 was predicted in the early part of the 20th century on the basis of the periodic table, and that the element was reported as discovered in natural samples by x-ray emission spectroscopy in 1925 and called “masurium” (Ma). These reports, however, invariably call this discovery erroneous and sometimes refer to the investigators (typically left unnamed) as “deluded”.

The original reported discovery of “masurium” was made in an exhaustive investigation of some thousand mineral separates of Nb-Mo-U-rich phases involving early elegant use of wavelengthdispersive x-ray microanalysis.