Manganese (Mn) : Manganese was discovered in 1774 by Swedish chemist John Gottlieb Gahn. Its name is derived from Latin word magnes meaning magnet. Its principle ore pyrolusite is paramagnetic.    Occurrence: It is 12th most abundant element on earth crust. Its important minerals and ores are pyrolusite (principal ore) while other ores are rhodochrosite, frankliniteManganese-Important Transition Element