Hi, I am having my car machine polished by a friend who does it for a living.. To help out, I have said I would prep the car for him as best I could by removing all tar spots and 'clay' the car which I've done before loads of times.

I am having a little paintwork done before he comes and have also removed all badges from the bonnet, tailgate and boot to make life easier (I'm also replacing them with new ones as they were all looking a bit tired).

I was preparing the matt finish panel on the boot today (the bit with RANGE ROVER written on it) and was a bit concerned when my clay bar turned dark grey! Can anyone advise what to do with this finish? I'm guessing it's not lacquered so I'm not going to do any more to it until I know the best thing to do..

Cheers,
J