Hi there: Does anyone know what these are and how I can get them off? I have thin black smudges above the second screws (when the laptop is facing me), matching on the base and on the monitor frame. It almost looks like that magnetic black sand stuff they have in kids' discovery museums. The ones on the monitor frame will rub off with spit (gross, sorry), but the ones on the base won't seem to come off. They're about 1/4" - 1", running right along the dark gray plastic casing, but on the aluminum. After I get the ones off of the monitor frame, they reappear. If I'm able to get the ones on the base to be any less apparent, they get darker over time. Clearly not the biggest deal in the world, but curiosity overcomes me.