Fine-mud stone formed from the fine mud between rocks peculiar to the Taihu Lake valley, under natural wind abrasion for hundreds of years. The stone texture is hard and not crispy, so it is easy to take shape. Water is not easy to dry in it. A breath can turn into ink which is rapid and does not damage pens. Because the material of the fine-mud carving is unique and fine, it is much of regional features of Suzhou. In combination with Chinese traditional cultures (calligraphy and painting), the fine-mud carving has values of watching, art, science, culture, economy and collection etc, so it is a rare work among ink-stones. Cangshu fine-mud ink-stone has antique shapes, simple patterns and straight lines. There are simple and unsophisticated nine-edge ink-stones, ancient bottle ink-stones, rectangle fret pattern ink-stones and dew-in-melon ink-stones etc; there are vivid ancient coin ink-stones, mushroom ink-stones, bamboo joint ink-stones and tree stump ink-stones etc; there are ink-stones with both form and spirit, like nine-turtle lotus leaf ink-stones, pavilion ink-stones, crab ink-stones and cattle ink-stones etc.