Explanation

It is called cyan glaze for short. It is a kind of green glaze with iron content of 1% -3%, which is fired in a high-temperature reducing atmosphere. After being fired with a reducing flame, some Fe3+is reduced to Feh, and the ratio of the two is called the reduction ratio. This ratio is related to process factors such as firing atmosphere, stopping temperature, and cooling rate. The hue of the celadon glaze varies greatly. In addition to the reduction ratio, it is also related to the formula of the glaze, the thickness of the glaze layer, and the content of Ti02 and P2O5. In addition, the existence of a large number of small bubbles and calcium feldspar in the crystal in the glaze layer has a great influence on the tone of the traditional green glaze due to the background effect of the body color. There are two kinds of Chinese traditional glazes: lime glaze and lime alkali glaze. The celadon glaze on the original porcelain before the Song Dynasty, including the Shang Dynasty, was lime glaze. Most of the celadon glazes after the Song Dynasty belong to lime-alkali glaze. The celadon glazes of both Guan and He kilns have cracks, commonly known as split glazes. This is a special decoration method which is intentionally made by taking advantage of the different expansion coefficients of the body glaze. There are ice cracks, caviar patterns, crab claw patterns, hundred garbage patterns, cowhide patterns, etc. The celadon sleeve is thicker than the general transparent glaze. The thicker the glaze layer, the darker the glaze color. However, if the glaze layer is too thick, the glaze will flow, causing defects such as crow's feet or cracking.

Classification