aged background decay iron metal rust rusted rusting rusty steel surface texture brown metal rust abstract green grunge metals old oxide structure wheathered contrast oxidation paint painted decorative door welding wrought iron bar city grungy iron bar iron bars rusty metal urban urban decay Cleveland girder girders growth life plant rivet rivets corrode corrugated disintegrate sheet cable diagonal rope spool twist twisted winch wire blue grate grates manhole pile sewer stock stockpile textures