The color of cashmere does make a difference in quality in that fleece that comes off the goat a dark color must be bleached before it can be dyed. Bleaching tends to make the cashmere brittle. If the cashmere is naturall white or light colored, it can be dyed without bleaching, preserving more of its softness. You may notice when you flip through the swatch cards in high end suit-makers' custom boxes, you'll frequently see cashmere swatches of any color marked, "Prime White Cashmere." The message is, the cashmere started out white and was not bleached. I don't mean to supercede any of the previous posters who made valuable observations about fibre length, etc.