How to Clean a Penny With Malic Acid
- 1). Pour some lemon juice into the bowl. The liquid should rise high enough so that a penny can be fully submersed.
- 2). Sprinkle some salt into the lemon juice. Don't add so much that the salt cannot dissolve completely in the lemon juice.
- 3). Place a penny in the lemon juice and wait 5 minutes.
- 4). Remove the penny from the lemon juice and rinse it under warm water.
- 5). Dry the penny with a paper towel.
- 6). Put a small amount of baking soda on the surface of the penny and rub it into both sides with a paper towel. This will bring back the shine of the copper after being cleaned.
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