Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature often in combination with iron, and in many minerals. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels. Manganese ores may accumulate in metamorphic rocks
or as sedimentary deposits, frequently forming nodules on the sea floor.
Manganese is a grey-white metal, resembling iron. It is a hard metal and is very brittle, fusible with difficulty, but easily oxidized. Manganese metal and its common ions are paramagnetic. While manganese metal does not form a permanent magnet, it does exhibit strong magnetic properties in the presence of an external magnetic field. Manganese is essential to iron and steel production by virtue of its sulfur-fixing, deoxidizing, and alloying properties.
Small amounts of manganese improve the workability of steel at high temperatures, because it forms a high melting sulfide and therefore prevents the formation of a liquid iron sulfide at the grain boundaries.