What is Rhodium?

Rhodium was discovered in 1803 by William Hyde Wollaston, who isolated it from platinum. He named it after the Latin word rhodon, meaning rose. Wallaston was also the discoverer of palladium. Rhodium holds the distinction of being the world's most expensive precious metal. It costs about six times as much as gold by weight. Rhodium is never found in mineral form, only being found in trace amounts within platinum or nickel ores. 80% of the world's rhodium comes from South Africa, and world production of the metal is only about 20 tons per year. Part of rhodium's appeal comes from its high reflectance, almost unique among the metals. Rhodium electroplating is used, especially on jewellery, to provide a surface that will resist scratches and tarnish, and give a white, reflective appearance.