I always prep my fabric before I use it. I’m not too worried about shrinkage as most of what I do is toys so that’s not an issue but I am careful about removing the excess dye out the fabrics. During the week I did my usual soak fabric in hot water then wash. When I went to iron them today I discovered one of the fabric had colour dye marks on it. I suspect it happened in the washing machine as I had 3 shades of pink in the machine at once. When I soaked them I did have the dark piece in a separate bucket but in the machine they never seem to have an issue. I don’t think the piece was like this when I brought it. Luckily it was only in a couple of areas on the fabric and I was able to cut out what I needed from other parts although on one small section I’m hiding the colour mark on the inside of what I’m making as it’s not visible on both sides. I’m not sure why this happened this time or why it didn’t colour the 3rd piece of fabric which was lighter than this but it is a lesson learned to pay close attention when I’m ironing the fabric that there are no imperfections in the fabric before I cut it out and start stitching with it. I’d hate to spend all the time cutting and stitching only to find out the fabric had dye marks or a misprint in the pattern.