What is "davyum"

Davyum \Da"vy*um\, n. [Named after Sir Humphry Davy, the English chemist.] (Chem.) A rare metallic element found in platinum ore. It is a white malleable substance. Symbol Da. Atomic weight 154.

n. A supposed chemical element discovered in 1877, later found to be a mixture of iridium and rhodium.

Davyum was the proposed name for a chemical element found by chemist Serge Kern in 1877. It was shown that the material was a mixture of iridium and rhodium. In 1950 it was proposed that the new metal might also have contained rhenium, which had not been discovered in Kern's time.