Why rust forms in asphalt pavement and how to treat it.
It may sound awkward but yes, asphalt pavements also rust -- or more correctly they develop rust spotting and steaking. It is more common that you may want to acknowledge and is seldom addressed in sealcoating bids because most sealcoating professionals, and for that matter property owners, believe that such spots can be effectively remedied by sealcoatings.
That is a totally false assumption.
Sealcoatings may cover and hide rust spots for a few weeks but they do come through eventually. The rust spots start coming through as shiny, silvery spots which turn brown with ageing. If left untreated they will eventually cover the sealed surface with unsightly brown streaks and exploded rust aggregates.