A solution of two parts white vinegar and one-quarter part salt to two parts of water is a good brass cleaner. When boiling, it removes corrosion from brass soaked in it. The next steps are rinsing the brass in water and air drying it to prevent further corrosion.
Homemakers should not use vinegar-based brass cleaner on lacquered or embellished brass. The vinegar may harm lacquer, while boiling damages embellishments. If the finish is unknown, it's best to assume that the brass is lacquered. If the brass is tarnished, it is probably unlacquered.
The best way to clean lacquered brass is to wash it with a solution of dishwashing liquid in warm water, using no more of the wash solution than necessary. Following the wash, the homemaker should wipe the brass with a clean damp cloth to remove soapy residue and to dry it thoroughly. Wiping with light mineral oil may remove dirt that washing didn't remove, but it's wise to test the oil in an inconspicuous place first to be sure that it will not harm the lacquer.
Once unlacquered brass is clean, it is ready for polishing with a paste of equal parts of salt, white flour and white vinegar. The homemaker should rub the paste onto the brass, wait one hour, and then rinse and dry the brass before buffing with a soft cloth.