In the 1990s, a "crystal cup" was unearthed from the Warring States Tomb, and when my friend saw the news, he couldn't help but say: "Isn't this the cup that I bought milk from the supermarket?" Although this statement makes people can't help but be funny, it still makes many people question this, "Could it be that the cup brought in by modern tomb robbers was left in the Warring States tomb?" This statement is very convincing, and the onlookers are deeply impressed.
After expert identification, the "crystal cup" in the Warring States Tomb is indeed made of crystal, not a modern glass, which makes everyone convinced that this "crystal cup" is indeed a cultural relic of the Warring States period. In fact, the appearance of glasses in the Warring States tomb is not unusual, because at the end of the Warring States period, there was already glass on the mainland, and it is likely that it is still homemade glass; if you trace the origin of glass, there is glass as early as around 4000 BC, so it is not unusual for China to import glass before 4000 BC.
Look for glass origins from artifacts
In 1975, Shaanxi Baoji unearthed a number of glass tubes and glass beads from the Western Zhou Dynasty, proving that glass had appeared on the mainland at a very early age.
At the same time, in the Warring States tombs in many parts of the country, a large number of glass has appeared, such as the tomb of Zeng Houyi in Suixian County, Hubei Province, the tombs no. 3 and No. 278 of Jiangling Yutaishan, etc. Not only are these large tombs of nobles unearthed with glass, but also in some small tombs of the Warring States, glass also appears. It is enough to prove that in the Warring States period, the production and use of glass on the mainland has a certain degree of extensiveness, not limited to the aristocratic community.
In some famous tomb relics, it is not difficult to find the figure of glass, for example, the sword of Yue Wang Gou Jian and Wu Wang Fu Cha have glass inlays, especially on the sword of Gou Jian, you can see that the inlaid glass has obvious artificial deformation process, the glass pattern on the sword, there is an obvious mold shape, such traces let us not difficult to see that the glass at that time has its own processing ability, it can be seen that at that time, there were already some processing technology.
So, is the glass in these tombs our own glass, or is it imported from abroad? To understand this problem, we must start with West Asia, where glass first appeared, to see if continental glass and West Asian glass are the same thing.
The battle between import and self-control
The earliest discovery of glass in the mainland is the Xinjiang region, due to the special location of Xinjiang, it is inevitable to think of Xinjiang importing glass from West Asia, this speculation is not nonsense, after all, there are records of imported glass in historical materials, in ancient times, the earliest glass was called glass, which is a kind of glass.
"Coral, Tiger Ray, Liu Li, Lang Jiu, Zhu Dan, Qingbi... All foreign treasures are revealed. - Book of the Later Han Dynasty
In the Han Dynasty, this situation of imported glass has been recorded, and it can be seen from the text that the earliest glass is recorded side by side with coral, amber and other items, which shows that the early glass existed in the form of luxury goods, not applied to thousands of households. A large number of glass found in the Warring States tombs are in the form of small glass beads, and the popularity at that time should be the simplest glass beads, rather than a large number of glass craft products.
It can be seen that the glass in Xinjiang is most likely imported from West Asia, while the glass found in the Warring States tombs is not necessarily from Tibet or imported.
In order to more accurately find out whether Xinjiang glass and Warring States glass were imported from West Asia, we changed our perspective and began to analyze the chemical composition of the two kinds of glass.
After laboratory analysis, we learned that the glass in West Asia is generally soda-lime glass, and the glass in Xinjiang is also soda-lime glass, which shows that the glass in Xinjiang is indeed very highly likely to be imported from West Asia. The glass in the Warring States Tomb is not soda-lime glass, but lead barium glass.
This result has made many experts and scholars bright, and the composition of the Warring States Tomb Glass is obviously different from the West Asian Glass, that is to say, the Warring States Tomb Glass is most likely not imported. After many studies by experts and scholars and careful investigation in all aspects, a bold point of view was put forward - glass self-creation.
After this statement came out in the 1970s, it received widespread attention, with some voices saying that you can't prove that the Warring States Tomb Glass was self-created; there was also another voice that said that it proved that it was not imported, it was naturally self-created. Both views are argued endlessly, but neither can convince the other. Therefore, whether the glass in this Warring States tomb is homemade or imported has not been determined.
Ancient glass making
Although it is not certain that it is homemade glass, it is also true that the composition of the glass inlaid on the sword is significantly different from that of West Asian glass. With the excavation of more and more cultural relics, it was found that the glass products unearthed in Hubei are very similar to the chemical composition of the porcelain glaze unearthed in Jiangxi, is it true that the earliest glass making technology in the mainland comes from the porcelain glaze manufacturing technology?
From the perspective of enamel manufacturing technology and glass making technology, their production process is only poor in making glass that requires containers, if this is the case, we already have such technology in the Shang Dynasty.
Since there is technology, can it improve the transparency of glass? This is a question that people consider in the Warring States period, they remembered that in the Spring and Autumn Period, some people used the characteristics of lead dan and saltpeter to make medicinal materials, is it that lead dan and saltpeter have the same role in helping to melt when making glass? After research, this idea was confirmed, and a translucent glass called "dragonfly eye" was made, which is also the earliest lead barium silicate glass explored in the mainland today.
By the time of the Han Dynasty, it was already possible to make some larger areas of glass, such as lead barium silicate glass with a × of 32.5 cm× 14.8 cm × 3.5 cm and a weight of 5.25 kg in Shandong Jimo. The lead barium silicate glass is gradually popularized in the Spring and Autumn to the Han Dynasty in the mainland, and the technology is gradually improved, in addition to using lead to reduce its temperature and improve its fluidity, it also gradually tries to use saltpeter refined glass production process. By the Han Dynasty, potassium silicate glass had appeared, which can be confirmed by glass relics excavated in Guangdong and Guangxi.
In the Tang Dynasty, thanks to the introduction of "glass blowing" technology, the production of soda-calcium silicate glass was further developed and improved. The Song Dynasty gradually began to replace lead oxide with calcium oxide, and the furnace temperature at this time was able to reach a high temperature of 1400 degrees.
In the Yuan, Ming, and Qing dynasties, the production of glass was vigorously developed, and at the beginning of the Yuan Dynasty, it was basically potassium calcium silicate glass. Early glass factories also began to appear, and there were two main glass factories: the Imperial Glass Factory of the Forbidden City and the Zibo Glass Factory.
Despite this, at that time, glass products were generally hairpins, snuff bottles and other small pieces.
Glass from "treasure" to "popularization"
Glass in ancient times has always been regarded as a treasure, but also has always been a noble to have objects, this can be seen from the inlaid glass on the sword, glass in ancient value, until the Tang Dynasty has not changed, even so, the price of glass products in the Tang Dynasty is still high.
Funan Dagang came from the Western Tianzhu Kingdom to sell Quite Li Mirror, with a wide area of one foot and five inches, weighing forty pounds, and the inside and outside were clean, placing five colored objects on it, looking at it clearly, and not seeing its quality. Ask its price, worth millions of dollars. - "The Tale of the Four Dukes of Liang"
It can be seen from the "Records of the Four Dukes of Liang" that during the Tang Dynasty, a foreign "Po Li mirror" was still asking for a price movement of "millions of guan".
Until the early years of the Republic of China, glass really went from "luxury goods" to folk popularization, when the glass factory developed rapidly, there were more than 300 in Hunan Province alone, and more than 200 in Jiangsu Province.
Has been developed to today, glass products are varied, extremely high quality, affordable, into thousands of households, as my friend said, even if you buy a carton of milk in the supermarket, you will give away a glass of good quality, and such a glass, if you get it in ancient times, it is nothing less than a treasure!
In summary, you can see that in fact, "glass" has appeared before the ancient Warring States period on the mainland, so it is not necessary to exclaim when seeing the "crystal cup" in the Warring States tomb, but it is worth mentioning that the "crystal cup" unearthed in the Warring States tomb is indeed made of crystal material, not "glass" as we understand it. Glass was highly sought after in ancient times, mainly as ornaments and handicrafts, and was not widely used, which is a pity.
△ Text/Noshi Diary
References: The Book of the Four Dukes of Liang, The Book of the Later Han Dynasty