Do you use a Parker fountain pen? A Parker 51 pen’s nib has iridium in it.
The discovery of iridium is very similar to that of osmium. Scientists dissolved platinum in aqua regia, only to find a dark insoluble residue that resembled graphite forming in the liquid. Smithson Tennant, an English chemist, noticed that the residue contained two elements osmium and iridium in 1803. In 1804 he published his work and officially named both elements that he had accidentally discovered.
Iridium is a very hard and brittle metal. It is one of the densest elements, second in density only to osmium. Iridium is one of the rarest metals and the most corrosion-resistant one. Therefore, it is used for deep water pipes and for the contacts in spark plugs. The element has utility in spacecraft engineering and telescope manufacture. Iridium is a member of the platinum family, and is white in colour, with a yellowish hue. Though it is not abundant in the earth’s crust, Iridium’s presence in meteorites is considerable. Due to the difficulty in extracting iridium, there are not many industrial applications for the element. However, its alloys are used widely. Iridium’s atomic number is 77, and it is represented as Ir.
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