Found this: "Shot cotton is special because the warp and weft yarns are 2 different colors woven together to create a special depth, a “shot” of color. When the edge of this fabric ravels, you can see a bright contrast to the body of the fabric." at this link:
http://www.spoolsewing.com/blog/2008...otton-scarves/
Also found this: 'These fabrics are woven using cotton thread which is dyed in small batches. Variations in color and small imperfections in the weaving are a natural part of the process, and to be expected. Tonal warp and weft create soft and subtle color effects.'
Now that I've seen a picture I realize I've used this before. It feels like regular very good quality quilting cotton, maybe a little tighter and silkier, at least the ones I've had. Very lovely and sort of glows when you move it around because you get a glimpse of the contrasting warp or weft thread.
I don't know if they come in different qualities or weights, but if it's the Kaffe Fassett collection you're looking at, I would trust it absolutely. The quality has always been wonderful in my experience. I love his collections.
Good luck and have fun!