Create a mixture:
Take 1 tablespoon of white vinegar and 1 table spoon of table salt and stir it well in 1 cup of hot water. Make sure that the salt is completely dissolved in water. Take a very fine steel wool and dip it in the solution created. Now rub the corroded areas by using the steel wool. Ensure that you are using very fine steel wool. Otherwise, you will end up creating scratches on your sink, which will look really bad. In fact, the scratches will be the replacements of the corrosion in the sink, which you will never want to happen.
Image courtesy: acklandsgrainger.com
Polish the sink:
After you are done with the cleaning process, rinse the sink well and make sure that it gets completely dry. Now take a good quality brass polish and apply it to the sink by using clean rags. The polish will help the sink to keep away from corrosion in the future.
Image courtesy: motherearthnews.com
If you find verdigris on your brass sink, you can use a mixture of baking soda and hot water. Take ½ cup of baking soda and mix it well in 4 cups of hot water. Now apply the solution using your hands. Make sure you wear rubber gloves before applying the mixture. Rinse and dry, and your sink looks new again.
Image courtesy: rgbstock.com