When brass is new and shiny; there are few things prettier. However, brass you've left alone over a period of time can become dirty and tarnished. With a little patience and care, you can easily restore your brass item to its original beauty using household ammonia.
Remove the lacquer layer. In order to properly clean the brass, you must remove the protective layer of lacquer. Apply a commercial lacquer removal solvent, if your item's heavily tarnished.
Wash the brass item in diluted ammonia and water. Once you remove the lacquer, it's easier to get rid of the unwanted tarnish by washing it in a diluted ammonia and water solution. Rinse the brass piece with clean water once the tarnish is gone.
Use straight ammonia if the brass is badly tarnished. If you find the weak ammonia and water solution is not strong enough, increase the amount of ammonia, using straight ammonia if necessary.
Soak severely tarnished brass pieces in the ammonia for about an hour. Check on it every ten minutes or so. Ammonia is a strong cleaning solvent and may erode some of the brass. If your brass item is engraved, remove it from the ammonia before the ammonia has had a chance to eat away at the engraving.
Rinse the tarnish-free brass item thoroughly with clean water to remove all traces of the ammonia.
Polish your brass item. Now that the brass is clean, it's time to return it to its original beauty. Using your favourite brass polish, shine your brass item.
Make sure the area is well-ventilated. Ammonia is a strong-smelling, caustic substance.
Always use rubber gloves to protect your hands from ammonia's corrosive quality.