Rhodium is a chemical element with the symbol Rh and atomic number 45. It is a rare, silvery-white, hard, and chemically inert transition metal. Rhodium is a member of the platinum group of metals and is found in platinum or nickel ores, as well as in the by-products of other metal refining processes. It has a high melting point and is highly resistant to corrosion and wear, making it an ideal material for high-temperature electrical contacts and furnace elements. Rhodium is also used as a catalyst in many chemical reactions, including the reduction of harmful exhaust gases in catalytic converters. It is one of the most expensive precious metals, due to its rarity and difficulty in obtaining large amounts of it.