Ruthenium

Ruthenium is a hard, silvery metal in the platinum group and one of the rarest elements in Earth's crust. Karl Ernst Claus isolated it in 1844 and named it after Ruthenia, a Latin name for Russia, where he worked. It is recovered as a byproduct of refining platinum, mostly in South Africa.

Electronics is its largest use. Combined with oxygen as ruthenium dioxide, it forms the resistive layer of the tiny chip resistors on the television's circuit boards. Ruthenium also coats electrical contacts, has been used in hard disk platters, hardens platinum and palladium jewelry, and speeds up many chemical reactions as a catalyst.