Question:

Some of my earrings leave green marks on my ears. How can I prevent that?

Answered by dermatologist Jennifer Adams, MD:

First of all, know that the green residue isn't harmful and can be washed off your skin with soap and water.

This can happen with multiple types of metals, usually copper. If you think about copper-plated pennies or the copper-covered Statue of Liberty, you'll notice a green discoloration over time. The green color is from a chemical reaction called oxidation between the copper metal and things like water or chemicals.

The same reaction can happen with your jewelry. Some jewelry is made of copper, with silver or gold on top. What happens is, the copper in the jewelry reacts with our sweat or lotion or other products. But it can also happen with a lot of other metals, too, it's just less frequent with those.

So what can you do to prevent that strange green residue? If you've worn off the protective outer layer, you can get the jewelry recoated with the precious metal.

You also can cover the jewelry with a clear coat of nail polish, which will prevent the metal from reacting. You do have to reapply the nail polish every so often.