This is a rust-preventing coating compound consisting of a color dispersal agent and ferromanganese (said ferromanganese being in a proportion by weight of iron and manganese of 40/60 - 10/90), and said ferromanganese being 40-80per thousand by weight of the compound. The color dispersal agent is an alklysilicate, or epoxy resin. Up to 15per thousand by weight of the ferromanganese powder can be substituted by zinc. This invention was created as an improvement to the use of zinc in so-called zinc rich paint. Zinc brought about problems when it was used in the past (such as the formation of white rust on steel). This invention, though, has overcome such problems.