Iridium is a chemical element with symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, iridium is the second densest element (after osmium). It is also the most corrosion-resistant metal, even at temperatures as high as 2000C.

Atomic Weight:  56
Density:        765 g/cm3
Melting Point:  65.65 °C
 Boiling Point: 78 °C