I've noticed these black dots on these particular rims for early-year Rodeos/Troopers a lot. I'm not talking about the dirt on top of the shiny silver (hey it's winter)... I'm talking about the black dots that simply won't rub off. They've been there for years now, but what is that ? I tried aluminum wheel cleaner, etc. but nothing works. Any ideas ?

[Linked Image]

http://www.rh71.com
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