Nail marks
The use of the form of branch nail support firing is quite common in the Song Dynasty "official kiln" nature of the kiln mouth, such as Ru kiln, Xiu Nei Si official kiln, suburban altar under the official kiln, etc., the Song Dynasty official Longquan kiln mouth also has a very small amount of use. The use of nails in the Chuanshige kiln is quite common, which is also an important basis for defining it as an official kiln system.
The nail marks are the traces left by the separation from the utensils after the use of the nail kiln tools and when they leave the kiln. Shaped like a small crater, it is a cross-section of a fulcrum wrapped in a glaze, slightly protruding from the plane of the glaze.
The nail marks on the porcelain of the Chuanshige kiln are quite different from the nail marks on other kiln porcelain. Ru kiln nails are small, such as the size of sesame seeds, commonly known as "sesame nails", the section is sesame grain shape or oval, mostly milky white. The nail marks on the Southern Song Dynasty official kilns are slightly larger than those of the Ru kilns, and the cross-section is round, mainly black and gray. The nail marks on the Chuanshige kiln are slightly larger than those on the official kiln porcelain, and the section is round or oval, with black gray, gray and brown colors, and most of the soil is coarser.
Song Dynasty Aoi Kou Plate
Collection of the Palace Museum in Beijing