How to Clean Brass Tarnish With Baking Soda

Brass is composed of differing amounts of zinc and copper, including "basic" brass, which is made from 33 percent zinc and 67 percent copper. As brass ages, it takes on a darker coloring, or tarnish. Tarnishing occurs when air reacts with the metal, leading to the deepening of copper's color, or patina. Removing tarnish is safely accomplished with a mixture of baking soda and white vinegar.

...
Soak heavily tarnished brass pieces in a baking soda and vinegar mixture.

Step 1

Pour 1/2 cup baking soda, 1 cup white vinegar and 2 tbsp. table salt into a small bowl.

Step 2

Mix the ingredients together well. Dip the corner of a soft cloth into the mixture.

Step 3

Apply a thick layer of the paste onto the brass piece. Allow the mixture to remain for 10 minutes.

Step 4

Rinse off the paste with cool water. Buff the brass item with a soft cloth. The reaction caused by combining the acidic white vinegar and sodium in the baking soda and salt dissolves the tarnish.