Palladium is a precious metal, one of the platinum group metals (PGM), which typically are found together in ore deposits. It was named after the asteroid Pallas, which was discovered at about the same time. Together with rhodium, ruthenium, osmium, iridium, and platinum, palladiums form a group of elements referred to as the platinum group metals (PGM). Palladium is used extensively in jewelry-making in certain alloys called "white gold". It may be alloyed with platinum or substituted for it. It is used in watch bearings, springs, and balance wheels and also for mirrors in scientific instruments. Although palladium is considered a precious metal and it is used in jewelry, the most significant applications of palladium are of industrial nature. Because of its corrosion resistance, a major use of palladium is in alloys used in low voltage electrical contacts. When it is finely divided, palladium forms a good catalyst and is used to speed up hydrogenation and dehydrogenation reactions.