Cleaning shells with muriatic acid is something I had put off for a while, but once I finally tried it I was addicted! This is the second time I'm doing this to my shells and the results are just fantastic. That being said, using muriatic acid isn't the only way to clean your shells. Mineral oil can also be used to bring back the color, so I wanted to see how shells would look after using muriatic acid compared to using mineral oil to bring back the color to sea shells. I was actually pretty surprised by the results!