Atomic Number: 77
Atomic Weight: 192.217
Melting Point: 2719 K (2446°C or 4435°F)
Boiling Point: 4701 K (4428°C or 8002°F)
Density: 22.42 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6
Group Number: 9
Group Name: none
Iridium has two isotopes, Ir-191 and Ir-193 and both are used in the production of radioactive material. Ir-191 is used for the production of radioactive Ir-192. This Ir-192 is used as a radiation source in gamma cameras that are used for non-destructive testing. Ir-192 sources are also used in so-called brachytherapy procedures whereby radioactive materials are placed in close contact with the tissue being treated. Although Ir-192 can be produced from natural Ir, the use of enriched Ir-191 gives a much higher specific activity and allows the use of smaller sources. The use of Ir-193 has been suggested for the production of the therapeutic radioisotope Pt-195m.