Thanks for the replies. The photos lost some quality . The yellow & flaking stuff is paint . Under the paint there is a white ceiling board .. between the ceiling board and the red terracotta they used some sort of plaster type stuff ..thing is it is white in some places - grey in others . The water damage made it "bubble" which in turn makes it look a little grey sand & cement mix ..there aren't much that's visually identifiable as fibrous .. more like gritty or sandy. Well I guess I had better get a sample tested. Or just paw off the job onto a tradesman and let them decide if it looks suspicious.