Check out this link:
http://veritaserum.com/media/2004/08/13/galerieslafayette.shtmlThere is a picture of some HP costumes on display at a gallery. One of the costumes is a complete, uncut Hermione sweater. I'm sure that the costume department had more than one set of clothing for the different scenes, but it's made me wonder whether the swatches in the costume cards really do come from costumes that were worn during filming.
Does anyone know how Artbox obtained the costumes and props, and how we can know for sure that they really were used in the movie? It's something I've wondered ever since I found out that LOTR costume cards are made from leftover fabric, and not the actual garments worn during filming.