The following uses for manganese are gathered from a number of sources as well as from anecdotal comments. I'd be delighted to receive corrections as well as additional referenced uses (please use the feedback mechanism to add uses).
- used to form many important alloys. In steel, manganese improves the rolling and forging qualities, strength, toughness, stiffness, wear resistance, hardness, and hardenability. With aluminium and antimony, especially with small amounts of copper, it forms highly ferromagnetic alloys. Manganese metal is ferromagnetic only after special treatment
- the dioxide is used in the preparation of oxygen, chlorine, and in drying black paints
- the dioxide (pyrolusite) is used as a depolariser in dry cells, and is used to "decolourise" glass that is coloured green by impurities of iron. Manganese by itself colours glass an amethyst colour, and is responsible for the colour of true amethyst
- important in the utilisation of vitamin B1
- the permanganate is a powerful oxidising agent and is used in quantitative analysis and in medicine