Watercolours were often thought of as a prerequisite study sketch before a much bigger oil painting took place. But they are, thankfully, a category within their own right. The Chinese were the original masters of using this very precise delicate way of applying paint. For it to flow and work properly a sequence of layers are built up to a harmonious range of iridescent colour combinations with deft brush marks to create and image that is interesting and captivating. A good watercolour should always look fresh and spontaneous and that is where the skill is duly noted.