How to Clean Pennies with Vinegar [and Turn Them Green!] - Mombrite Put all the pennies in the salt and vinegar solution and wait about 5 minutes. Take half of the pennies out and put them on the paper towel in the dish. Take half of the pennies out and rinse them with water. Put them on a separate piece of paper towel to dry. After about an hour, look at the pennies in the dish and the pennies that were rinsed ...