Manganese · element 25
The metal that makes steel workable, glass colourless, and every green leaf release oxygen
Key facts
Manganese is one of the unsung workhorses of the industrial world. About 90 per cent of it goes into steel, where it removes oxygen and sulfur from the molten metal and toughens the finished product. Without manganese, steelmaking as we know it would not work, and there is no good substitute.
It also has a quieter role. At the heart of the photosynthesis machinery in every plant is a cluster of four manganese atoms that splits water and releases the oxygen we breathe. And the oldest cave paintings used black manganese oxide as a pigment, so it has been in human hands for tens of thousands of years.
Where it is found
Manganese is around the twelfth most abundant element in the crust, and its main ores are the oxide minerals pyrolusite and psilomelane and the pink carbonate rhodochrosite. South Africa holds the largest reserves in the Kalahari manganese field, and Australia, Gabon, China, Brazil and Ukraine are important producers. Pure manganese metal is never found in nature.
The deep ocean floor is scattered with manganese nodules, potato-sized lumps that grow over millions of years as metals precipitate from seawater. They also contain nickel, copper and cobalt, and there is fierce debate about whether they should be mined. Manganese is an essential trace element for all living things. People need a few milligrams a day, easily obtained from whole grains, nuts, tea and leafy vegetables.
How it was discovered
Pyrolusite was known for centuries as a glassmaker's material, first for colouring glass purple and then, oddly, for removing the greenish tint caused by iron, which earned it the name glassmaker's soap. Chemists in the 1700s suspected it contained a new metal. Carl Wilhelm Scheele studied it closely in 1774 and concluded that it must, though he could not isolate it. His friend Johan Gottlieb Gahn did so the same year by heating the oxide with charcoal. Torbern Bergman, in whose Uppsala laboratory both men worked, had also argued for the new element and is sometimes credited with it. The name comes from Magnesia, a region of Greece, and for a long time manganese and magnesium were muddled together.
What we use it for
Steel comes first. Manganese is added to virtually every batch, usually as an iron-manganese alloy, both to clean the melt and to strengthen the finished steel. High-manganese steels are extremely tough and are used for railway points, rock crushers and safes. Aluminium drinks cans contain about one per cent manganese to improve strength and corrosion resistance.
Manganese dioxide is the positive electrode material in ordinary alkaline batteries, and manganese is part of many lithium-ion battery cathodes, especially in electric cars. Potassium permanganate, a deep purple oxidiser, treats drinking water, disinfects wounds and cleans fish tanks. Manganese compounds colour glass and ceramics, and manganese was once used in a petrol additive to raise octane.
Reading the numbers
Manganese melts at about 1246 °C, noticeably lower than its neighbours chromium and iron, and boils at about 2061 °C. Its density of 7.21 g/cm³ is close to iron's. The configuration [Ar] 3d5 4s2 gives seven outer electrons and a half-filled d shell, which is why manganese has more oxidation states in everyday use than any other transition metal, from +2, which is pale pink, through +4 in black manganese dioxide, to +7 in purple permanganate. Its first ionisation energy of 717 kJ per mole is a little higher than chromium's, reflecting the extra stability of a full 4s pair and a half-filled 3d shell. Manganese is unusually brittle for a metal because of its complex crystal structure at room temperature, so it is rarely used on its own. It sits in group 7 of the d-block, between chromium and iron, exactly halfway through the first transition series.
Safety and the environment
Manganese is essential in small amounts but harmful in large ones. Breathing manganese dust or welding fumes over many years, a risk for welders and miners, can cause manganism, a condition with tremors and movement problems that resembles Parkinson's disease. High manganese in drinking water is a concern in some regions with manganese-rich groundwater. Environmental impacts come mainly from mining and steelmaking, and any decision to harvest deep-sea nodules would affect ecosystems that are still barely understood.
Did you know?
- The oxygen released by every plant, alga and cyanobacterium comes from a water-splitting cluster containing four manganese atoms in the protein called photosystem II.
- The ocean floor holds vast fields of manganese nodules, which grow by only a few millimetres every million years.
- Black pigments in the Lascaux cave paintings, around 17,000 years old, are manganese oxides.
- Although it sits right next to iron, manganese is not magnetic in the everyday sense; it is only weakly attracted to a magnet.
- Robert Hadfield's manganese steel of 1882 was the first alloy steel to be commercially important, and it is still used for railway points because it hardens as it is hammered.
- Potassium permanganate is its own indicator in titrations: the purple colour vanishes as it reacts, so no extra dye is needed.
More in the transition metals
Column-mates come first, since elements in one column have outer electrons arranged in a similar way and tend to behave alike; the rest are the nearest neighbours in the family.
See all 38 transition metals on one page, or browse all 118 elements.
Compare Manganese with another element
Each comparison has a side-by-side data table and a plain-English summary of the differences.
Frequently asked questions
What is manganese used for?
Overwhelmingly for making steel, where it removes impurities and adds toughness. It is also in alkaline and lithium-ion batteries, in aluminium cans, in fertilisers, and as potassium permanganate for water treatment and disinfection.
Is manganese the same as magnesium?
No, though the names share a root. Magnesium is a light group 2 metal that burns with a white flame; manganese is a hard, brittle transition metal used in steel. Both names come from Magnesia in Greece, where minerals of each were found.
Is manganese magnetic?
Not in the way iron is. Pure manganese is paramagnetic, meaning it is drawn very weakly towards a magnet but does not stick. Some manganese alloys, however, are strongly magnetic.
Is manganese toxic?
Small amounts are essential and food provides all you need. Long-term inhalation of manganese fumes or dust, mostly a workplace risk for welders and miners, can damage the nervous system, so exposure limits exist.
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Written by Anthony. Updated September 2026. Numerical data from Periodic-Table-JSON (CC BY-SA), cross-checked against the Manganese reference article. Spotted an error? Tell us.