Looks acid bathed to me, but there's no mention of how it was done. Mudguards are stainless GB, don't think those rust like that naturally.
Could also be oxidizing paint.
Also the frame is aluminium.. So it must be just paint.
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Looks acid bathed to me, but there's no mention of how it was done.
Mudguards are stainless GB, don't think those rust like that naturally.