Abrash is a Farsi word that means "cloud". The color variations is caused by using vegetable dyes on wool which causes inconsistency in colors. Abrash also helps to replicate the old antique rug that has released colors over time and now has variations of colors. Now days, abrash is considered acceptable in a handwoven rug since it provides a multiple of color palettes which provides flexibility to match with furniture fabrics. Abrash is considered undesirable for extremely precise and fine rugs.