Some silly sod decided it would be a good idea to chop some aluminium trunking with an angle grinder right next to my motor at the weekend

. After running outside to have a polite word with the mentally challenged individual I took a quick look at the paint; no damage, and went back inside.
Next day I noticed marks on the windows where it seems sparks of molten aluminium attached themselves to the glass, they didn't wash off, scratched at a couple with my thumbnail and the flakes of metal come off with a bit of effort, leaving light marks on the glass.
I'm going to need to polish these marks off, (or as close to it as possible) any idea how ?
