Rust treatment. Brush being used to apply a rust removing mix of chemicals to a rusty spanner. Many commercial mixes of chemicals are available to remove rust (iron oxide). Most of them use strong acids, so skin contact should be avoided. If left, the acids will also corrode the original metal, so the chemicals should be washed off soon after use. If the rust has only affected the surface, the appearance of the original metal can be restored. However, if the rust has deeply corroded the metal, then scars and pits will be left in the metal. The use of an oil or wax coating will help prevent future cases of rusting.