How to Naturally Clean and Polish Copper at Home

Using copper utensils, containers and kitchenware has some unique benefits from killing germs to balancing your doshas. But the miracle metal does come with its drawbacks – when exposed to air and moisture copper metal can undergo a transformation due to the oxidisation process (similar to how rust can damage iron and steel), leaving it tarnished and removing the lovely glean. Although oxidised copper may not look as appealing – it’s actually protecting the copper by forming a protective outer layer that prevents further corrosion (as opposed to steel rust, which flakes off and can weaken the steel). This can be seen with copper roofs, pipes and statues that have changed from their original reddish-brown colour to a distinctive blue-green colour, known as Verdigris. A well-known example of this is the Statue of Liberty in New York.

Copper Tarnished Royal Observatory of Edinburgh
Different levels of tarnish can be easily seen on the Royal Observatory of Edinburgh

For a lesser known, but perfect contrast of oxidised against non-oxidised copper, the Royal Observatory in Edinburgh – which was built in 1896 – still has much of the original copper work displayed on the towers. In 2010 it was refurbished and some of the copper panels were replaced, this makes it easy to see the difference the oxidation layer can have on the look of copper.

More important than the look though, the oxidation layer is unstable when it comes in to contact with some substances (many which are used in cooking such as vinegar and baking soda), and can easily leach into a meal. Although copper is an essential trace element for many bodily functions, ingesting too much can become toxic and cause some problems in the body. For this reason, copper utensils, serving dishes, pots and pans should always be maintained to ensure this Verdigris oxidation layer is prevented.
Luckily, it’s quite easy to remove oxidation from copper and can be done using a variety of easily obtainable items that you probably already have in your pantry.

The best homemade copper cleaning mixes

1. Salt and Vinegar

Rubbing method:

If your copper items are delicate or highly polished, be gentle when using salt as it can cause small scratches in the metal. To ensure this doesn’t happen use fine salt and fully dissolve it before rubbing on the copper, using a fine cloth or sponge (not a sourer or steel wool/brush).

  1. 1. Mix up a concoction by dissolving a tablespoon of salt into a cup of white vinegar
  2. 2. Using a rag or cloth you can rub your copper objects with the mixture.

This should get rid of most surface level tarnish quite quickly, when it’s nice and clean wash with soap and water and wipe with a clean towel.

Boiling method:

For copper that is heavily oxidised or has small, hard-to-reach places, you can instead use heat to help remove the tarnish.

  1. 1. Add the tablespoon of salt and a cup of vinegar to three cups of water (or make enough to submerge your copper objects).
  2. 2. With your copper items fully immersed, boil the solution until the tarnish is removed.

Remove the copper objects from the solution and allow them to cool, then wash with soap and water and dry with a clean towel.

2. Tomato Sauce/Ketchup

Yes, as surprising and unlikely as it sounds, you can put that bottle of Heinz to work on tarnished copper as well - this is useful for delicate items as there is no abrasive grains that could cause scratches.

  1. 1. Get some sauce onto a clean towel or sponge and dab and rub the copper to clean. The acidic pH of the sauce will quickly remove the tarnish from your copper items.
  2. 2. When you’re happy with how clean and fresh your items look, rinse off the sauce with water and wipe with a clean towel or cloth.

3. Lemon and Salt

Lemon Fruit:

This is a great way to clean copper pots, pans and other less delicate items, the acidic lemon will mix with the oxidised copper and quickly remove it.

  1. 1. Cut a lemon in half and add some salt to the inside of the fruit, then rub this on your copper to see the tarnish easily lift away.
  2. 2. Once done rinse away the residue with soapy water and wipe clean with a cloth.

If you have delicate or highly polished copper you can try cleaning it with a sliced lemon without adding salt (the coarse salt could leave the surface of the metal with tiny scratches) and rubbing.

Lemon Juice:

  1. 1. Make a paste with equal parts lemon juice and baking soda then add a add some salt into the mix.
  2. 2. Use a cloth to dab the paste onto your copper and rub it to clean the tarnished layer off.
  3. -- You might find it useful to rinse with water periodically to see the progress.

When finished, rinse a final time with water to remove the paste and residue then wipe with a clean cloth.

4. Baking Soda

Baking soda can be used wet or dry to clean away tarnish, but again, be careful with delicate or polished items – similarly to salt, the coarseness of baking soda could leave some scratches on the metal.

  1. 1. To use dry simply sprinkle some baking soda onto a cloth and rub the copper to scrub away the oxidation layer.
  2. 2. Or add some water, lemon juice or vinegar to the baking soda, try out different consistencies depending on what you’re trying to clean.

When finished rinse away any residue with water and wipe dry with a clean cloth.

The best homemade copper polishing recipe

The oxidation process of copper begins as soon as it’s exposed to the air, and works even faster in extra moist and salty environments (such as near the ocean). So, to minimise the effect you should take care of your copper utensils after you’ve used them.
If your copper is clean but just looking a bit dull, keep it luscious and elegant by polishing periodically with a lemon juice-salt solution.

  1. 1. Fully dissolve a tablespoon of fine grain salt into a cup of lemon juice
  2. 2. Dip in a clean cloth and rub the solution onto the copper – the gleaming surface should show through with little effort.
  3. 3. Rinse with water and make sure all the acidic lemon juice is removed.
  4. 4. Dry with a clean cloth then buff with a fresh cloth to bring out the shine.

This mix is great because by using fine salt and allowing it to dissolve completely the tarnish will be removed easily but there will be no scratches or damage to the surface of the copper.

Preventing Copper Tarnish and Oxidation

If your copper is not going to be used frequently, you’re storing it or it’s a display item, you can put a light coat of oil to slow down the tarnishing/oxidation process.
Ensure the copper is completely clean and dry, buff it with a clean dry cloth to bring out the gleaming colours, then using a clean cloth wipe a light coating of baby oil or mineral oil over the surface.
Try to make sure all of the metal is coated evenly to prevent some parts oxidising faster and leaving uneven splotches.

Cleaning copper after use

When cleaning copper that is used frequently, wash with warm soapy water then rinse, making sure there’s no residue or any foreign particles left on the surfaces. Then wipe dry with a clean cloth.
Leaving anything such as food bits, acidic solutions, or even water on the copper surface can speed up the oxidation process and create splotches and marks where parts of the copper are more tarnished than others.
For the perfect glistening finish, use a soft cloth to wipe your copper dry, then use a second fresh cloth to buff and polish it.