After a few a days from the last cleaning, some "red" stuff appears around my bathroom faucet knobs. Can anyone help explain why? I'll clean every few days with just warm water and Dawn soap but then it appears again. Even when I clean it, while the redness will disappear it appears there's still "stuff" around the knob (instead the color is whiteish/yellowish color). How can I clean this without harming my countertop, which is Quartz. Also, once I can clean, will caulking around the knob help prevent the same issue happening in the future? Before and after pictures attached. The first picture is before I clean the countertop and the 2nd and 3rd shows what it looks like after cleaning. While the faucet never turns red, it appears there's still some sort of stuff on there.