Iridium

77
Ir
192.22


iridium.jpg (5656 bytes)
Iridium is used Helicopter spark plugs.

Properties

Symbol Name Atomic Number Atomic Weight Group Number
Ir Iridium 77 192.22 9

Description

Standard State: solid at 298 K
Color: silvery white

Iridium was discovered by Tennant in 1803 in the residue left when crude platinum is dissolved by aqua regia. Iridium, a metal of the platinum family, is white, similar to platinum, but with a slight yellowish cast.  It is very and brittle, making it hard to machine or work with.  It is recovered as a by-product from the nickel mining industry. Iridium is also used for electrical contacts.  Its principal use as a hardening agent for platinum.