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{{Element | name=Iridium | symbol=Ir | anumber=77 | amass=192.22 amu | state=Solid | class=Transition Metals | cstructure=Face-Centered Cubic| color=Silver | date=1803 | discname=Smithson Tennant | origname=From the Latin ''iridis'', meaning ''rainbow''. | uses=Used in conjunction with [[osmium]] to tip gold pen points, to make crucibles and other high-temperature containers. Also used to make alloys  for standard weights and measures, as well as heat-resistant alloys. In addition, used in cancer irradiation, hypodermic needles, helicopter spark plugs and as hardening agent for [[platinum]]. | obtained=Found in gravel deposits with [[platinum]], [[iridosmium]], and [[osmiridium]] ores. }}

{{Element | name=Iridium | symbol=Ir | anumber=77 | amass=192.22 amu | state=Solid | class=Transition Metals | cstructure=Face-Centered Cubic| density=22.560 g/cm^3 | color=Silver, slightly yellowish | date=1803 | discname=Smithson Tennant | origname=From the Latin ''iridis'', meaning ''rainbow''. | uses=Used in conjunction with [[osmium]] to tip gold pen points, to make crucibles and other high-temperature containers. Also used to make alloys  for standard weights and measures, as well as heat-resistant alloys. In addition, used in cancer irradiation, hypodermic needles, helicopter spark plugs and as hardening agent for [[platinum]]. | obtained=Found in gravel deposits with [[platinum]], [[iridosmium]], and [[osmiridium]] ores. }}

'''Iridium''' is an [[element]] in the [[transition metal]]s class of the [[periodic table of the elements|periodic table]].  It is hard and lustrous, and resists attack by acids.  It is very dense (22.560).  It has two stable isotopes.

'''Iridium''' is an [[element]] in the [[transition metal]]s class of the [[periodic table of the elements|periodic table]].  It is hard and lustrous, and is perhaps the most corrosion-resistant metal known.  It has the second-highest density of all elements, after [[osmium]].  It has two stable isotopes.

 

An alloy of [[platinum]] and iridium was used in the international standard [[meter]] bar, before the standard was changed in 1960.  A similar alloy is still used in the international standard [[kilogram]].

[[Category:Elements]]

[[Category:Elements]]