Iridium
Atomic symbol: Ir
Atomic number: 77
Atomic mass: 192.22
Appearance: Silvery white solid at 25°C
Group: 9
Period: 6
Series: Transition metals
Block: d
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d⁷ 6s²
Extremely dense, hard and brittle.
Fun Fact! Due to the high abundance of irium discovered in ancient rocks, it has been hypothesized that the extinction of dinosaurs, amongst other life forms, occured as a result of an iridium-containing comet stricking the Earth at the point in history that the rocks are dated.
