I recently purchased an HK 25 by CompLyfe in the Rose Gold plating from a friend for a hell of a steal. He had the tube sitting around for 7 months or so without using it, I thought it was beautiful and wanted it so we made it happen. Fast forward a couple weeks and I'm noticing an area just about an inch above my switch with a blotch of dark "fairing"? Its so minor my camera doesn't pick it up but I notice it immediately. Upon looking around I can't find much of anything as far as caring for Rose Gold mech tubes.. Can you help? I need to know what I need to properly care for it, and is this "fairing" or darkening in the finish permanent or can it be polished out?? Any help is appreciated!!