Molybdenum - 42Mo: historical information
In 1778 Carl Welhelm Scheele conducted research on an ore now known as molybdenite. He concluded that it did not contain lead as was suspected at the time and reported that the mineral contained a new element that he called molybdenum after the mineral. Molybdenum metal was prepared in an impure form in 1782 by Peter Jacob Hjelm.