Glassware is a vessel made of glass. Glass art has maintained a continuous development history of thousands of years in our country. During the Wanli period of the Ming Dynasty, the production of materials in Boshan, Shandong was very prosperous. It was introduced to Beijing in the late Ming and early Qing. In the early Qing Dynasty, during the Kangxi, Yongzheng, and Qianlong periods, the production of colored glaze was once revived. A large-scale “Liuli Factory” produces feeders for the royal palace. During this period, the variety of glassware was rich and colorful, and the shape and decoration also changed. Among them, bottles, bowls, snuff bottles, birds and beasts made of imitating jade, jade, agate, coral, etc., are vivid in color and have a unique style and charm.
Glassware is mostly made of soda lime silicate glass, which is colorless and transparent. The iron content in the glass is generally less than 0.02%. Adding coloring agent to glass raw materials can make colored glass; adding opacifier to make opalescent glass (see Glass Manufacturing). Potassium lead silicate glass, also known as lead crystal glass, is used to manufacture high-end art utensils such as goblet, perfume bottle, fruit bowl and so on. This kind of glass contains PbO, has high refractive index and dispersion, it is especially bright when the edge surface is ground, high specific gravity, and it makes a crisp sound when struck. PbO content of more than 30% is full lead crystal glass, PbO content of 24-30% is medium lead crystal glass, PbO content of less than 18% is low lead crystal glass, and BaO-containing barium crystal glass. Cooking utensils such as coffee pots and other products use heat-resistant borosilicate glass, which has a low coefficient of thermal expansion and strong resistance to rapid temperature changes. Glass-ceramics have better heat resistance and resistance to rapid temperature changes, and high mechanical strength, which is suitable for making cooking utensils and utensils that are often washed in hotels.
