Shape, Material, Color, Spirit
Although Mi Fu’s four categories are well-suited for describing Taihu Rocks, they are not comprehensive enough, and with the appearance of newer gongshi types, modern connoisseurs generally apply another set of criteria for judging rocks. These four are shape (xing), material (zhi), color (se), and spirit (shen).
Shape (xing)
The first consideration for a rock is that it should be naturally shaped. Display rocks can then be divided into two groups: abstract and representational. The former gives more room for the imagination and are admired by many people. But rock lovers also appreciate representational rocks which can be subdivided into those representing landscape and those representing particular objects. Landscape representational rocks resemble hills, scenes after snow, cliffs and peaks. They can be further subdivided into those representing near or far distant scenes. The latter should exhibit proportion between height and width to give a proper framework for the vista represented. Rocks resembling particular objects, such as human figures and animals may either bear such likeness in shape or spirit. The merit of the latter is that they both resemble and yet do not resemble a given object.