How to clean pots and pans in copper?

I got pots and pans stainless steel christams, but funds are copper. Since I've used on a regular basis, they are now turning colors. How do I get these back to the clean copper color?

Cut a lemon in half and dip it in salt plain. Rub the copper, rinse it and watch it shine LIKE NEW! Be sure to rinse well as the lemon is acidic. Do not clean the oven it will ruin your pans. This method is also non-toxic and easy.

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