This is a poly-cotton damask which I used quite a bit of brown on. It is actually a deeper colour than it looks on the photo. (By the way, the reason I know they've all got some polyester in is because I got my soldering iron and burnt them - the ones that stuck have got polyester in them! Less risky than setting them alight with a match...). I'm saving all my cotton for dyeing, not that there's much left from all the previous dyeing playdays...