Iridium

Iridium
Properties
Atomic symbol	Ir
Atomic number	77
Classification	Transition Metals
Atomic mass	192.22 amu
Other Information
Date of discovery	1803
Name of discoverer	Smithson Tennant
Name origin	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 from	Found in gravel deposits with platinum, iridosmium, and osmiridium ores.

Iridium is an element in the transition metals class of the periodic table. It is hard and lustrous, and resists attack by acids. It is very dense (22.560). It has two stable isotopes.