Do you need to clean your copper mugs? It’s very simple and even if you’re unable to remove all of the tarnish it’s not going to kill you [that I know of.] There are a few options for cleaning your copper mugs at home with items that you most likely already have around such as ketchup, vinegar and salt. I used some white vinegar, sea salt and a paper towel to rub the mug down and remove almost all of the tarnish. To get to the harder to reach areas, or if your mugs have small dents then you can just use a toothbrush.