Having made sails of the same weight and feel as the corsair sails, the material I used had a sort of rubbery backing that bonded it together, so maybe the sails are bonded together in some way so they feel like fabric, but because of what is used in the process it would smell if the iron was too hot.
(Does this make sense?)
I think the curtains from the mansion are made of a type of felt.
Elaine