What's the difference between coloured glaze and glass? [encyclopedia of life]

In ancient China, glass was called "Liulin", "Youzi" and "colored glass". Since the Southern and Northern Dynasties, it has also been called Boli. According to the records in Guangya and Ji Yun, for a long time, "glass" was a general term for glass beads and other transparent substances burned by fire. Since the Ming and Qing Dynasties, people have called "coloured glaze" opaque, which is of course different from glass.

There is a simple and touching folk song called "On Mulberry" in Yuefu of Han Dynasty, which describes the simplicity and beauty of Qin Luofu, a girl who picks mulberry, and says, "There is a temple above her head and a bright moon beside her ears." This kind of perforation cannot be used as "bright moon pearl" or glass for hair accessories. In the past, many people thought that the ancient glass in China came from abroad; In fact, china glass's production technology has its origin, which has been confirmed by a large number of grading materials in recent years.

At the latest, in the Western Zhou Dynasty more than 3 100 years ago, our physiognomy began to master the glass manufacturing technology. A large number of glass tubes and glass beads were found in the tombs of Zhuangchungou in Luoyang, Henan Province and Rujiazhuang in Baoji, Shaanxi Province in the early Western Zhou Dynasty. Experts at home and abroad have identified lead-barium glass in China and soda-lime glass in the west as two different glass systems by modern spectroscopy. This fact shows that ancient glass in China was independently manufactured with a unique raw material.

China glass's invention is closely related to bronze smelting technology. This is the conclusion drawn by the researchers of Beijing Glass Research Institute after analyzing the color, transparency and composition of glass in the western period. The main raw materials of bronze are malachite, tin ore and charcoal, and the melting temperature is about 1080℃. Glass usually refers to silicate compounds that are melted, cooled and solidified. Quartz sand is the main raw material for melting glass, and other raw materials include soda ash and limestone. The melting temperature is 1200. In the process of smelting bronze, due to the melting of various minerals, glassy substances will appear in the discharged copper slag, which are filamentous or massive silicon compounds. Because some copper particles invaded the glass, the glass appeared light blue or light green. These translucent and bright substances have attracted the attention of craftsmen, and they can be made into exquisite glass decorations with a little processing. In this way, after long-term continuous practice and exploration, people finally mastered the glass making technology and laws.

In ancient China, glass was called "Liulin", "Youzi" and "colored glass". Since the Southern and Northern Dynasties, it has also been called Boli. According to the records in Guangya and Ji Yun, for a long time, "glass" was a general term for glass beads and other transparent substances burned by fire. Since the Ming and Qing Dynasties, people have called "coloured glaze" opaque, which is of course different from glass. More than 2,000 years ago, when Zhao Nvdi, who was said to know how to dance, lived in Zhaoyang Hall, "most of the windows were glazed with green, so the hair could not be hidden". Explain that at that time, transparent doors and windows could shine brightly. When Emperor Wu of the Han Dynasty, who liked "immortals", "rose from the shrine to the shrine", all the doors and windows were stained glass, and the lighting was thorough. It can be seen that the so-called "window bright and clean" is not modern. As for the Liu Liping, the glass vessel, the glass bowl recorded in Shi Shuo Xin Yu and the glass clock mentioned in Cui Hongchuan in Jin Shu, they have also been unearthed in the tombs of Western Zhou Dynasty in Tunxi, Anhui Province and Shaoshan, Hunan Province during the Spring and Autumn Period and the Warring States Period. Bowls, hooks, seals and other glassware are common in Han tombs. A glass wall with a diameter of 234 mm, an aperture of 48 mm, a thickness of 18 mm and a net weight of 1.9 kg was also unearthed near Maoling, Emperor Wu of the Han Dynasty in Xingping, Shaanxi. After modern spectral analysis, it belongs to lead-barium glass.

By the Northern Song Dynasty, the level of glass technology had made great progress. 33 pieces of cultural relics glass bottles with paper-thin walls and crystal-clear walls unearthed from Peiji in the Northern Song Dynasty in Dingxian County, Hebei Province; Polished glass unearthed in Tianchang, Anhui Province, and hundreds of egg-shaped glass bottles unearthed in Mixian County, Henan Province are all evidences of the technological progress of glass manufacturing and the advanced level of blown glass in the Northern Song Dynasty. After the Song Dynasty, the types of glassware increased, and their uses were more closely related to people's lives. The Ruins of the Yuan Dynasty Glass Workshop in Ruoqiang, Xinjiang and the Boshan Glass Workshop in Shandong at the end of Yuan Dynasty and the beginning of Ming Dynasty are the earliest glass workshops discovered in China.

During the Ming and Qing Dynasties, the glass production centers were located in Shen Yan Town (now Boshan County), Guangzhou Port and Jinggang in Zichuan County. In the Qing Dynasty, the Palace Glass Yard was set up in Kangxi, which has been able to produce transparent glass with more than 15 colors and monochrome opaque glass. Silk-wrapped glass, colored carved glass and snuff bottles in the Qing Dynasty are all treasures of glass art in the world.

Although China ancient glass was invented independently, it developed slowly and always maintained its inherent characteristics. It has the advantages of bright colors and sparkling, but it also has the disadvantages of being light, brittle, brittle, not resistant to high temperature and not suitable for rapid cooling and heating. This is because its main components are lead and barium, and its firing temperature is low. Lead-barium glass is not suitable for making tableware, but only suitable for processing into various decorations, ritual vessels and funerary objects. Therefore, compared with ceramics, bronzes and jade articles, glassware is narrow and underdeveloped.

China ancient glass was invented and manufactured by local craftsmen alone. It has a long history, exquisite shape and unique ingredients. However, compared with western ancient glass, China ancient glass is still at a disadvantage in origin time and use. Archaeological findings show that the glass fragments unearthed in Asmar can be traced back to about 4,300 years ago. Glassware appeared in the two river basins about 3600 years ago. Soda-lime glass has always been the main ancient glass in the west, with good temperature resistance and strong adaptability to rapid cooling and heating. 2600 years ago, glass manufacturing technology was very popular in Europe and the Mediterranean coast, and its products spread to China through the western regions (now Xinjiang). Since the Northern Wei Dynasty, through the Tang, Song, Yuan, Ming and Qing Dynasties, we have continuously absorbed and learned the western glass adaptation technology. For example, Fang Yizhi in the Ming Dynasty said in "Introduction to Physics": "Zheng He, the eunuch of Sambo, once brought a western glass burner". Since then, mass production of glass began in the Ming Dynasty. The palace glass field established in the Qing Dynasty once hired many European glass craftsmen as guidance to manufacture high-grade art glass. These measures not only promoted the development of china glass's manufacturing industry, but also reflected the mutual exchange of science and culture between China and foreign countries. The glass manufacturing industry has really fully developed, and it is still like this today.

Reference:/3601/2004/08/26/109@279993.htm.