Cleaned this unique roof today. On initial glance, it looks like a old school ceramic/asbestos tile roof, but its actually individual metal tiles.  Cleaned up at 1% with two to three coats.  We also cleaned the big "Marshmallow" pool dome in the photos too, inside and out.

Found a new type of mask at Harbor Freight. Don't know if it would be considered as good as a respirator, but it does have charcoal filters, and worked like a charm for the three hours we spent inside the dome. Very comfortable!