when I used polish I got the same thing on other
mods as well. So I decieded that keeping things shiny might be making those marks faster. With the oils on our hand mixes with the chemicals from the polish caused it to blacken faster. I highly recomend using a metal cleaner. And keep cleaning it until the cloth or rag shows no more black. then use a buffer for nails to get that shine you want. THis will help keep the black to a minimum. All that black stuff is oil and salt build up from your hands.
Also keep your hands clean using dawn (degreaser) after using lotion or eating. Doing this before using your GG or any
mod will also help with build up of oils.
Since doing this method several months ago with my GGT I only need to clean it once every two weeks besides the button. The brass is a different story though.
