Yikes!!! Just found out that the lipstick red/orange fabric I’m working with was dyed with heat sensitive dye. (As shown - one triangle has not been pressed, the other was overpressed for illustration.). Oh, and I forgot to mention - it’s LINEN. I am thankful to report that the effects do seem to fade with time. I carefully re-pressed it to make sure it was evenly heated which should also help to avoid problems. This is why testing your fabric first is always a good idea. I am also thankful it is only an accent fabric!