Copper tarnishes through oxidation — the warm reddish-orange metal darkens to brown and eventually develops a green patina (verdigris). Tarnish is purely aesthetic on decorative copper; on copper cookware, it doesn't affect cooking performance. Copper responds well to mild acid treatments using ingredients most homes already have.
Salt and Lemon Method
- Cut a lemon in half and sprinkle salt generously on the cut face
- Rub the salted lemon directly on the tarnished copper surface — the citric acid dissolves tarnish and the salt acts as a mild abrasive
- Work in circular motions, squeezing slightly to release more juice as needed
- For pots and larger items, squeeze lemon juice into a bowl, add salt, and use a cloth to apply the mixture
- Rinse thoroughly with warm water
- Dry immediately and completely — copper retarnishes quickly when left wet
Ketchup Method
- Apply a thin layer of ketchup to the tarnished copper surface — the tomato's acidity breaks down tarnish
- Allow to sit for 10–30 minutes (longer for heavy tarnish)
- Scrub with a soft cloth or sponge
- Rinse well and dry immediately
Vinegar and Salt Paste
- Mix white vinegar with salt and a small amount of flour to form a paste
- Apply to the copper and allow to sit for 10 minutes
- Scrub with a soft cloth, rinse, and dry immediately
Copper Cookware Notes
- Most copper cookware sold today is lined with tin or stainless steel — clean only the exterior copper; the interior lining is cleaned as you would any pot
- Never use steel wool on copper — it scratches the surface
- Some people prefer the natural aged patina on copper — cleaning is a personal preference, not a requirement
- Copper mugs (Moscow Mule cups): same methods apply; dry thoroughly after every use to prevent interior tarnishing