Ruthenium

Ruthenium is a rare, hard, silvery-white transition metal in the platinum family. It resists attack by many chemicals and does not tarnish under ordinary conditions. In nature, it occurs alongside other platinum-family metals in ores, including deposits in South Africa and nickel ores in Canada. It is recovered as a by-product of processing platinum, nickel, and copper ores, then chemically separated from the accompanying metals. Small additions of ruthenium make platinum and palladium alloys harder, helping electrical contacts withstand wear. Its compound ruthenium dioxide is used in tiny electronic resistors, components that limit the flow of electric current. These uses show how even small amounts of a rare element can play an important role in everyday technology.