IRIDIUM is one of the six platinum group metals which occur together in nature. It is the second member of the series of transition elements in the periodic table and has an atomic number of 77. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance, and corrosion resistance. Filing Code: IR-1. Producer or source: Engelhard Corporation.