What is the development process of glass production technology in China?

Like bronzes and ceramics, glass has a long history and was first developed in the Qin Dynasty. At first, the glass was very rough and inferior. During the Northern Wei Dynasty, the technology of burning glass in kiln was further developed. During the Tang and Song Dynasties, most important buildings were decorated with glass, such as cornices, kisses, cicadas and flat thorns. The corner of the house is very prominent, with the cornice facing upwards. Later, this process was gradually improved and developed into what it is today.

In ancient China, the production of coloured glaze was passed down from generation to generation, or it was passed down from master to apprentice. Due to the limitation of history and the influence of traditional ideas, the firing process of glass, especially the glaze formula, has been kept secret. Craftsmen have the habit of "father and son, father and son, glazed don't pass on their surnames" and "father and son don't pass on their daughters". This technology will be lost for a long time. In addition, in the feudal society of China, these skills were neglected, and it was difficult to enter the classics, which brought difficulties to future generations.

Many glazed utensils in the Song Dynasty are small and exquisite, and their shapes are more abundant than those in the previous generation. In addition to glass bowls and bottles, there are innovative forms such as glass flowers. Glass is made of artificial crystal by dewaxing and casting. The main process is to heat the intraocular lens to a high temperature close to 1000℃, so that it has fluidity and flows into the precast gypsum template for molding. Gypsum formwork is made by removing wax patterns by heating, so it is called dewaxing casting.

Traditional glass has only been sought after by Chinese and foreign collectors in recent years. The emergence of a new generation of glaze artists once again proves that the art of glaze laying has not disappeared with the trend of the times. According to folklore, Fan Li came across stained glass while supervising the creation of The Legend of the King. He gave it to Shi as a token of love. Tears of stone flowed through this masterpiece, so people called it "flow" and later turned it into glass.