How do you get chrome off tiles?

Question:Whilst trying to fit in a shower door that was too big, a couple of tiles got chrome on them. What would be the best way to remove the marks, noting that we have allready tried cif and mr muscle.

Answers:
If you left chrome on the tiles, you left some nice sratches on the tiles as well, depending on if you tiles are painted or not, you may be able to use some acetone, I think that would be your best bet.