 The usual distinction made with "doucai", which also combines underglaze blue with overglaze enamels in other colours, is that in "wucai" only parts of the design include blue, and these cover wider areas, and are often rather freely painted.In "doucai" the whole design is outlined in the blue, even if parts are overlaid by the enamels and invisible in the finished product.Some parts may also be painted in the blue.