Oddly it's just the one wheel I have this on and there aren't corresponding gouges out of the edge of the rim, so I'm not inclined to think kerbing.

 

Looks like stone chips etc to me Graham. The corrosion starts out as small black dots which eventually join together looking like black "rust"

 

Ah ok. That would make sense, given the way it feels to the touch. Strange that it's only the rear offside though

Next question obviously, is it refurb-able ?

 

Dunno mate. Have you seen the thread about wheel refurbers and if so why not contat them and redirect them to this thread ask their opinion?

 

That is corrosion, some one has scraped the top of it to expsoe it further though!

That's refurbable no problem.
Only thing is you may struggle to get a colour match to the others it is often best to do them all!

 

Are you sure Mikey? I prefer Kelk's explanation. There's alot of scratching and they look like holes rather than pitting?

 

Problem is there is nothing wrong with the other three. More than 1 being a problem and I'd probably use it as an excuse to start saving for some 17s.

To the touch it feels like the lacquer's missing - and the striations leading away from each "hole" would reinforce that idea.

 

def not corrosion IMO. corrosion starts on the leading edge of the spokes. If there isn't any there - which there doesn't appear to be from your photos - then I wouldn't have thought what you can see is..

 

That assumes that debris grit blasts the leading edge and nothing else could have touched the face of the wheel

The problem has been made worse by some one scratching at them, causing the lines and exposing more area to air.

 

what looks like scratching could be where water has got under the laquer. are these wheels the ones with the polished perimiter?