I also learned the hard way! I made a beautiful wall hanging for my forever friend only to find out that the yellow chalk I used on white would not come out. I brushed it, washed it, did everything I could think of to get the yellow our but it would not come. So now the quilted piece sits in a drawer and was never given away. I am so afraid to use anything to mark my quilts now. No matter what anyone suggests I am too afraid to get that far again only to have the same thing happen.
