Coat your copper completely with ketchup. Work the ketchup into the tarnish with your fingers or use a soft bristled brush (an old toothbrush works well) to get into corners or into the item's design detail. For severely tarnished items, leave ketchup on for a few minutes.
Step2
Rinse your item thoroughly with warm running water. Rub gently to be sure to remove all of the ketchup.
Step3
Dry thoroughly with paper towels and admire the shine!