Many of us still have copper fixtures, pipes, flatware, kettles and other items in our home. This is because copper was used for everything from faucets to cookware to light plates for over a century before steel became affordable enough for use in outfitting homes.
If you own anything that is copper you know that the main problem is that copper is constantly oxidizing and creating a green patina. Although that slightly degraded aqua touch is actual an asset in cases (for instance it is very common on old Victorian roofs and on the turrets of post-modern buildings from the eighties) it does not look that appealing on a kettle, flower vase or a fork.
Most of the items that can be used to remove the chalky green coating on your copper items are ordinary household ingredients: white vinegar, salt and baking soda (or cornstarch.)
Copper cleans up very nicely if you immerse the item in a salt and vinegar bath. Simply mix one tablespoon of salt with three cups of water in a very big part. Take the copper item that you wish t clean and leave it in the pot. Leave the item there until the water and vinegar and salt solution comes to a full rolling boil. Leave the copper item like this until you can visually detect that all of the green color has left the surface of the copper. Then take the pot off of the heat.
Before you remove the copper from the pot make sure it and the water has cooled completely down to room temperature. Lift the object out of the pot and give it a quick wash with a high quality dish soap, like Dawn, to get rid of any vinegar smell that might be lingering on the item. Be sure to wash the pot you boiled the item in thoroughly as well.
If the problem is small then you might want to try cutting a wedge of lemon that has been sprinkled on both sides with salt. The salt acts like a scouring item. Scrub the green stain off of the copper item until it is gone and then wash the item with dish soap and water to get rid of any lemon debris.
You can also use ketchup to clean copper. Simply mix equal parts corn starch with ketchup to make a paste and then scrub the item clean. Be sure to wash and rinse the item with dish soap to eliminate any scent of ketchup.