Properties

Atomic Number	77
CAS Registry Number	7439-88-5
Chemical Symbol	Ir

History

The atomic number is 77 and the chemical symbol is Ir. The name derives from the Latin Iris the greek goddess of rainbows because of the variety of colors in the element information. Thes salt solutions. Iridium and osmium were both discovered in a crude platinum ore in 1803 by the English chemist Smithson Tennant. Iridium was discovered independently by the French chemist H. V. Collet-Descotils also in 1803. Descotils actually published one month before Tennant but Tennent is given credit for the discovery perhaps because he alone also found osmium in the ore.

Holden, Norman E., (2004). History of the origin of the chemical elements and their discoverers. National Nuclear Data Center. Retrieved from http://www.nndc.bnl.gov/content/elements.html