Cleaning Pennies Using Household Items

Cleaning pennies is a surprisingly popular topic. It is an easy science fair project, and there are quite a number of ways that people have come up with over the years to clean pennies. On top of that, there is an almost endless supply of dirty pennies around to work with, and the cost is cheap to get more. It also seems like pennies start to look dirty sooner than the silver coins in circulation in the US.

Here is a look at a range of ways we have seen to clean pennies. Some of these I have not tried, so if you experiment, please leave a note at the bottom with your results.

If you clean a vintage penny you will destroy any value that the penny has as a collectable. It will do no good to clean a valuable penny, so if in doubt get it assessed, or at least look it up in a coin price guide.

FYI, the pennies minted since 1982 are actually not copper pennies. The copper in pennies was getting to cost more than one cent, so the US Mint has switched to a compound of mostly zinc, with about a 2.5% copper content. Some of these cleaning approaches have some mild acid in them, which reacts more with the zinc than the copper pennies.

• Pencil Eraser - One of the easiest methods to try, is to clean the penny by simply rubbing it with a pencil eraser. This is surprisingly effective, and with one of the tools that has a long thin eraser you can clean quite a few. Try a draftsman's motorized eraser that has the eraser material spinning like a little Dremel tool. If you are worried about the abrasives that are in many erasers, then try a vinyl eraser.
• Vinegar and Salt - Make a mixture of one teaspoon of salt and one quarter cup of white vinegar, and let the pennies sit in it for just a few minutes. Of course the vinegar is a diluted form of acid, which in this case is the reactant, cleaning the pennies. A substitute of lemon juice also works for the acid in this mixture.
• Taco Sauce and Ketchup - Straight from Taco Bell, these are closely related and are one of the most mentioned. Some have reported the same type of success with mustard. As it turns out, the main ingredient in these vinegar and salt, so it's just another version of the one above.

Cleaning Pennies is a popular science fair project. Here is more information on science fairs

This is the coward's way out: commercial products are stronger than many of the solutions above and so you need to take care, especially with zinc pennies. Make sure you don't use such a strong solution that damage will be done.