Iridium (Ir)
Refractory Metals | Atomic Number: 77
Basic Properties
Ir
77
192.217 g/mol
| Element Category | Refractory Metals |
|---|---|
| Atomic Number | 77 |
| Atomic Weight | 192.217 g/mol |
| Crystal Structure | Face-centered cubic (FCC) |
Description
Iridium is the second-densest metal and one of the most corrosion-resistant metals known. It is extremely hard and brittle.
| Density | 22.56 g/cm³ |
|---|
| Tensile Strength | 2000+ MPa |
|---|---|
| Hardness | 6.5 Mohs |
| Melting Point | 2466°C |
|---|---|
| Boiling Point | 4428°C |
| Thermal Conductivity | 147 W/(m·K) |
| Electrical Conductivity | 2.09 × 10^7 S/m |
|---|
| Corrosion Resistance | Excellent - one of the most corrosion-resistant metals known |
|---|
Applications
Spark plugs, electrical contacts, crucibles for crystal growth, standard weights and measures, cancer treatment
Production Methods
Recovery from platinum group metal ores, electrolytic refining, chemical precipitation
History
Discovered by Smithson Tennant in 1803 along with osmium in platinum ore residues.