From the book:

"Strands of two rich, closely related shades of yarn are held together to knit the body of this bag.  The contrasting electric blue and green trim colors not only set off the main color, but provide interesting design features: The green scalloped border is tipped by small beads, and the blue rolled cuff forms a firm edging around the top.  The green and blue yarns tend to shrink a bit more during the felting, as well, which adds shape and security at the top of the bag."

Blue and green yarns are the Lamb's Pride Worsted, main body yarns are the Highland Style.