China's early porcelain appeared in the middle of Shang Dynasty in BC16th century. It is generally called "primitive porcelain" because it is still rough in the firing process of the carcass and glaze layer, and the firing temperature is also low, showing originality and transition.
Primitive porcelain was developed on the basis of pottery-making technology. In the Shang Dynasty ruins in Zhengzhou, Henan Province, many glazed porcelain statues, pots, etc. and fragments of these items were found. The fetal bone is fine and hard, the firing temperature is above 1000 degrees, and there is a metallic sound.
1980 a batch of primitive celadon fragments unearthed from Dongxiafeng site in Xia county, Shanxi province belong to the late Longshan culture more than 4000 years ago. A large number of celadon unearthed can be concluded that China supported the invention of porcelain in the middle of Shang Dynasty. At that time, the production of blue glazed porcelain was developed in the middle and lower reaches of the Yangtze River, and the glaze color was mostly bluish yellow, which was fired in an oxidation flame.
The celadon glazed porcelain in the Central Plains is mostly turquoise in color and fired in reducing flame. These primitive porcelains are made of kaolin, and the firing temperature is as high as 1 100~ 1200 degrees. The surface layer is sintered at high temperature and made into glass enamel which is firmly combined with the carcass. The tire is hard and delicate, with weak water absorption and metallic sound. There are statues, beans, jars, urns, bowls, etc.
Extended data
Shang celadon completely meets the basic requirements of porcelain.
First, kaolin is used as a tire.
Second, coat the surface with a layer of glass glaze. The main components of glaze are porcelain clay, limestone and plant ash, which are mixed into suspension and coated on the surface of porcelain blank. When it is baked in the kiln, it melts and forms a glassy substance.
Thirdly, the firing temperature reaches about 65438 0230℃. So far, the firing temperature of pottery is only 800℃~900℃, and a few of them reach 1000℃, while the firing temperature of porcelain is about 1230℃.
Fourth, pottery has water absorption, while porcelain has little or no water absorption. The water absorption of primitive celadon in Shang Dynasty was only 1%, or even lower. Because the content of silica (SiO2 _ 2) and alumina (Al _ 2O _ 3) in the matrix is above 70% and 65,438 07%, it is well sintered at a high temperature of about 65,438 0200℃, and its water absorption is very weak, which reaches the standard of porcelain.
Fifth, in terms of physical properties, such as specific gravity, hardness, and the degree of development of mullite (also called "mullite") crystals, it is the same as that of porcelain in the future. There was a clear metallic sound when knocking at the door.
All these prove that China porcelain was invented in Shang Dynasty.
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