Stonewash is a washing type of jeans.
In the stonewash process, the denim is put into a washing machine along with pumice stones. The fabric and stones are rotated together for a set period of time. The stones physically remove color from the fabric's surface, while the color at deeper positions remains. Thus, the contrast is increased. The final shade of the fabric is determined by the washing time. The longer the fabric is washed together with the stones, the lighter the shade will be and the more contrast will be achieved. The denim finally is rinsed, softened and tumble dried.