Verdigris is a greenish-blue discolouration on metals such as copper. Like rust, it occurs most often when the metal is left damp or stored in a humid environment. If you do not remove verdigris from your copper pots, it not only looks bad but will weaken the metal and eventually corrode the pots until they are unusable. Soap and water will not remove this, but other simple products can.
Pour vinegar into a clean spray bottle. Add 3 tbsp salt and shake the bottle gently to mix the solution.
Place the copper pot on paper towels to protect the work surface. Spray the vinegar and salt solution on the areas discoloured by verdigris. Let the solution remain on the pot for one minute.
Rub the pot with soft cloths, transferring the discolouration to the cloths. Repeat steps 2 and 3 until all verdigris is gone.
Rinse the pot in warm water and dry it with a soft cloth. Apply a commercial copper polish to the pot, using another cloth, to add shine to the copper.