Bicycles, cars, bridges
machines, magnets
Hardware tools, screws
Ammonia production catalyst

Iron is one the most useful metals. Its applications, as well as those of its alloys, are very important and well known, so are those of its compounds. The iron sulfate is used as fungicide, the oxalate of iron in photographic development, limonite and hematite as pigments and abrasives. Magnetite is used in the production of industrial electrodes, iron chloride and nitrate are used as mordents and industrial reagents mainly in the dye industry; "Prussian blue" and "turnbull blue" are used in the production of several types of inks. Iron carbonyl is used as catalyser of many reactions.