Mysterious red dust on my roof

[mitchie777]

Thanks for all your comments, consideration, thoughts and comedy. Red cinder dust is unlikely as I live in beaches and our roads, thanks to Fred redirecting PGT funds has pave our roads twice in a little over a year. I'm not a 'chemtrails' nut for the most part but considered it as much as I considered it to be from aliens. My confusion comes from how it has deposited on the surfaces of the roof. Nothing on the highest edges of the pitch of the shed style roof for about a foot or so. that makes me suspect wind and rain relieving the substance before it (organic/ohia blooms/dust from vog) degrades. Nothing under the over hang of the overlapping roof sections helps me conclude that it likely has fallen from the sky (vog dust/chemtrails/alien ship potty jetsam). My contractor suggested the mold thing but mold wouldn't likely form the sliding dripping running patterns on the slopes but an enveloping pattern and get all up in the cracks and corners and look like it was growing and creeping. Is there a way to post a pic on here or just links...? I could share a couple photos of what it looks like.