Prized for its relatively light weight and bright sheen, aluminum is widely used for manufacturing pots, pans and other metal vessels. It is a fairly soft, delicate metal and may develop a tarnished or dark appearance with age and use. The darkened appearance is not harmful, but it does detract from the metal's attractive appearance. Exposure to alkaline substances such as baking soda is the most common culprit when it comes to tarnished aluminum. The problem is simple to correct using household items, but it may return again over time if the local water is alkaline with a naturally high pH.
Wash the aluminum item in hot, soapy water to remove any obvious surface stains, food residue or other substances. Rinse it thoroughly and wipe it dry with a cloth before scrubbing off the tarnish.
Combine 3 tablespoons of soap flakes, 3 1/2 tablespoons of calcium carbonate powder, 3 tablespoons of white vinegar and 6 tablespoons of newly boiled water in a nonreactive ceramic or glass bowl. Stir it with a wooden skewer to dissolve the ingredients into a paste.
Dip the end of fine, 000- or 0000-grade steel wool into the cleaning solution. Gently rub the tarnished aluminum with the steel wool using a light, circular motion. Rub until the metal brightens and the dark, tarnished appearance is diminished. Focus more on badly stained areas to create a more uniform appearance in the metal.
Rinse the aluminum item thoroughly in hot, clean water to remove the cleaning paste, rubbing the surface to knock loose any stubborn residue. Inspect the surface; clean any remaining tarnished areas again using the cleaning paste.
Dab white vinegar onto any nicks or pits where the tarnish is embedded and difficult to remove. Let it sit for no longer than 10 to 15 minutes. Rinse the vinegar away using hot, clean water, then wipe the surface down with a clean dish cloth.
Wash the aluminum item in hot, soapy water and rinse it thoroughly before using it again. Wipe the interior and exterior dry with a clean dish cloth. Store aluminum in a dry location.
Prevent future tarnish on aluminum pots by boiling 2 tablespoons of cream of tartar and 1 quart of water inside every few months. Alternatively, cook acidic foods such as tomato sauce and tart fruit inside to keep the interior free from tarnish.