When marking small area's as I quilt, I have used a self-made pounce using cinnamon. Marks are usually gone by the time I get it quilted. I believe it was John Flynn on one of Alex Andersons long ago quilt show that gave this idea. I used a sq. of fairly loosely woven fab. with a tablespoon of cinnimon in the center, brought up the edges and tied a string around it. Couldn't see the marks when finished, but I do wash my quilts after quilting no matter what I use to mark. Hope this helps some.