Jules Henri Debray and Henri Étienne Sainte-Claire…

Jules Henri Debray and Henri Étienne Sainte-Claire Deville separate pure iridium from the platinum metals in 1874, while Henry Tresco and George Matthey, under the supervision of Debray and Deville, fuse and cast the standard meter in Paris using a ten percent platinum-iridium alloy. (Platinum will be used as an adulterant for gold at the beginning of the twentieth century, but it is now considered the more valuable of the two metals.)