They named element 75 rhenium (Latin Rhenus meaning "Rhine"). Rhenium was the last element to be discovered having a stable isotope.  The existence of a yet undiscovered element at this position in the periodic table had been predicted by Henry Moseley in 1914. In 1925 they reported that they detected the element in platinum ore and in the mineral columbite. They also found rhenium in gadolinite and molybdenite. In 1928 they were able to extract 1 g of the element by processing 660 kg of molybdenite. These achievements led to Walter and Ida being awarded the German Chemical Society's prestigious Liebig Medal in 1931. In 2018 a memorial medal "Fidelitas ad Scientiam" was issued by ISTR  for Anniversary of Re discovery   https://www.pinterest.ru/pin/747879081861611384/.