I don't recall these having a whitish color either<

While brass is a no-no I have may photos that show whitish wheels (usually just one) on engines and sometimes cars. Looks like whitewash and was use to magna flux (check for cracks in the wheels). They didn't bother to wash it off so it would turn the color of all other wheels in a short period.
Well it's sorta of an excuse!

Jon Miller
AT&SF
For me time has stopped in 1941
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