Apart from a small circle of technical specialists - predominantly metallurgists and chemists - Manganese is a little-known element. Yet it is the fourth most used metal in terms of tonnage, ranked behind iron, aluminum and copper. Around of 29 million tons of ore being mined annually (2004).
Manganese has numerous applications which impact on our daily lives as consumers, whether it be of objects made of steel, of portable batteries, or of aluminum beverage cans. In each case manganese plays a vital role in improving the properties of the alloys and compounds involved in each specific application.
One vital feature of manganese, which is not widely appreciated, is its role as an essential element in maintaining human health. Recommended daily dietary intake levels have been established by US regulatory authorities in an effort to ensure the maintenance of good health.
The exact role of manganese is not fully understood, but complex cellular reactions involving metallo-enzymes have been identified. Humans have well-developed homeostatic control mechanisms whereby manganese levels are regulated to keep them in the desired range. Medical research into conditions arising from an excess or deficit of body manganese is being carried out in a number of institutions.
Manganese has played a key role in the development of various steelmaking processes and its continuing importance is indicated by the fact that about 90% of all manganese consumed annually goes into steel as an alloying element. No satisfactory substitute for manganese in steel has been identified which combines its relatively low price with outstanding technical benefits. This is unlikely to change. After steel the second most important market for manganese, in dioxide form, is that of portable dry batteries.