by Smithson Tennant, Antoine Fourcroy, Louis Vanquelin, Hippolyte Collet-Descotils at 1803 in England, France. Origin of name
: from the Greek word "iris
" meaning "rainbow
Osmium was discovered in 1803 by Smithson Tennant in the dark coloured residue left when crude platinum is dissolved by aqua regia (a mixture of hydrochloric and nitric acid). This dark residue contains both osmium and iridium (named after the Latin word iris meaning rainbow because of the colourful nature of iridium compounds).