Paint the copper with a salt water solution.
Place it in a plastic bag, I used a black bin liner.
Put a pot in the bottom partly filled with something absorbent, paper
towel, sawdust, even unused cat litter ( I used a clean empty
margarine pot and paper towels)
Pour some Houshold Ammonia into the pot, fasten the top of the bag
and leave for a few days. Do this outside.
Boots sell the Ammonia, but have also seen it in Waitrose and hardware
stores. No need to clean the copper before you start.
Norma
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