Tarnish can be removed from brass with a homemade paste of vinegar, salt and flour. The mildly acidic vinegar combines with the abrasive salt to remove tarnish as the object is scrubbed.
Brass items are made from either solid brass or brass-plated steel. Care must be taken when cleaning brass-plated objects because scrubbing too vigorously or with a highly abrasive substance can remove brass right down to the steel.
Brass is often lacquered to protect the sheen. Lacquered brass should only be cleaned with a mild detergent. If lacquered brass is tarnished, it might be necessary to remove the lacquer finish before the tarnish can be removed.