Paint (or something similar) on rockers, how to remove?

I was driving past a rock quarrey the other day, and there was the usual dust and ash on the road. No big deal. But, after I washed it, I noticed that there were white specks all over my rockers and tupperware. It's some sort of paint I think. I tried to remove it with mineral spirits, but no luck. You can barely scrape the stuff off with your fingernail. Any suggestions on what to use to take this crap off?

BTW, my rear rockers are chrome.

 

[Bill Kemp]

Go to a Ziebart undercoating shop and get some of their solvent. That stuff takes off most anything I have picked up. They might let you try some before you buy it to see if it works.
Good luck...

 

[Hartman]

How much is it? Seems like everything at Ziebart = $$$

 

[Bill Kemp]

I dont know . They gave me some when they undercoated the X.
But if it works it's worth a lot.