Pottery is made of mud (clay), dried and then fired. It is the crystallization of mud and fire. Our ancestors knew about clay for a long time. As early as in primitive society, they could not live without clay everywhere. They found that clay soaked in water is sticky and plastic, and becomes hard after drying. The use and understanding of the history of fire is also very long. It was used about 2.05 million to 700,000 years ago in the Yuanmou era. In the long primitive life, the ancestors found that dry mud became more solid, hard and waterproof after firing, so pottery was produced. The invention of pottery has opened a new page for human beings to use, transform and confront nature, which is of great historical significance and a milestone in the history of human production and development.
According to the known archaeological data, the best quality pottery includes gray pottery in the late Paleolithic period more than 10,000 years ago, red pottery in magnetic mountain culture more than 8,000 years ago, painted pottery in Yangshao culture more than 7,000 years ago, "eggshell black pottery" in Dawenkou more than 6,000 years ago, white pottery in Shang Dynasty more than 4,000 years ago, hard pottery in Western Zhou Dynasty more than 3,000 years ago, terracotta warriors and horses in Qin Dynasty and glazed pottery in Song Dynasty more than 3,000 years ago. Porcelain production has developed rapidly, and pottery-making industry tends to decline. However, some special pottery varieties still have unique charm, such as Song and Liao tri-colors, teapot, glass, flowers and pottery sculptures in Shiwan, Guangdong, which are unique and have high ornamental value.
There are silicon compounds everywhere, from the hot molten material in the earth's interior to the cold surface, from dangerous rocks and valleys to the sand laid on the road. It is indeed the most extensive mineral in nature, and it is also the most noteworthy mineral, so human beings have been using it for a long time. The ancient pottery-making technology in China is an excellent example of using silicon dioxide. 1962, an early Neolithic cave was discovered in Dayuan Xianren Cave, Wannian County, Jiangxi Province, more than 10,000 years ago. More than 90 pieces of residual pottery were unearthed, all of which were red pottery with sand, with rough texture, seasonal patterns of different sizes, loose and fragile. Pottery pieces vary in thickness, and the tire color is mainly reddish brown, but also red, gray and black. The inner wall of the device is skinny, and there are no accessories such as ears and feet. These conditions show the primitive nature of pottery making at that time. The pottery unearthed from Laoguantai in Hua County, Shaanxi Province also reflects the same situation. The excavation of test stones fully proves that pottery was made in many areas in the early Neolithic period in China.
Yangshao culture in China was about five or six thousand years ago. At this time, the pottery was mainly red pottery, followed by gray pottery and black pottery. Red pottery is divided into fine clay red pottery and sand red pottery. The main raw material is clay, and some are mixed with a small amount of sand. Among Yangshao pottery, fine clay painted pottery was the most famous at that time because of its unique shape, red face, polished inside and outside and beautiful patterns. Exquisite clay reflects the level of pottery-making technology at that time, which is representative, so Yangshao culture is often called painted pottery culture in archaeology. The painted pottery dish unearthed in banpo village, Xi 'an is also the product of Yangshao culture.
At that time, the production of painted pottery, according to analysis, mainly went through four procedures First, laterite, sedimentary soil and black soil with good plasticity and operability are often selected, which become purer and finer raw materials after elutriation and precipitation. From the analysis of the unearthed painted pottery pieces, argillaceous pottery is not inferior to the later fine pottery. Second, make it worse. Painted pottery was mostly broken by hand at first. Small utensils are directly molded; Larger pottery, the body is not good, and it is generally made in two stages by mud tray building method. After the rough damage was made, the neck was fitted and the handle was embedded, and the process of making the damage was initially completed. Its shape is round and regular, with strong symmetry and wheel marks outside the wall. This shows that in the Yangshao culture period, slow-wheel pottery has begun to appear. Third, painting and ornamentation. Some finer painted pottery, before painting, often put broken pottery into very fine mud to cover it with a uniform pottery coat for painting. Painting is to paint colored natural minerals on pottery. The decorative patterns of pottery in Yangshao culture period were mostly printed with pattern woodcut. Fourth, burn kiln. According to archaeological data, there are mainly vertical caves and horizontal caves in Yangshao culture period. They are all composed of burner, fire chamber, fire channel, kiln chamber and so on. The flame burning in the fire channel reaches the kiln room. Because of the kiln room, the pottery in these two kilns is not barbecued directly on the flame, which is a great progress compared with the original bonfire or stove type. By analyzing the sintering conditions of unearthed pottery pieces, the sintering temperature of painted pottery reached about 950℃.
By the end of the Youshan period (about 2300 BC, it refers to the middle Neolithic cultural site excavated in Longshan Town, Zhangqiu County, Shandong Province), handicraft ceramics had developed greatly. The wheel system is widely used in the production method, and the shape is exquisite. The white pottery is made of kaolin. During this period, people have learned to give pottery various colors by using the gas characteristics in the kiln at the later stage of firing. During the Yangshao culture period, pottery was usually fired in an oxidation flame, and most of the iron in pottery was oxidized into high-priced iron and turned red. During the Longshan period, due to the reform of pottery kiln, when pottery was about to be fired, on the one hand, people suddenly added fuel and closed the top of the kiln, resulting in insufficient oxygen in the kiln. Pottery is baked in reducing flame, and most of the iron in the pottery is converted into low-priced iron, making the pottery gray or gray-black. Therefore, there were the most gray pottery products in Longshan culture period.
The carved white pottery and thin-shell white pottery that appeared in Shang Dynasty are particularly prominent. They are exquisite in texture, exquisitely carved, beautiful in shape, hard and durable. White pottery has these advantages, mainly due to the use of kaolin. Kaolin is mainly composed of aluminum silicate, with low iron content, fine material and strong plasticity. After high temperature firing, the appearance is white and beautiful. People's use and understanding of kaolin is related to the invention of porcelain later. If a layer of glaze is coated on the surface of pottery, it will not only make the surface smooth and beautiful, but also facilitate washing, especially for storing alcoholic beverages, and will not be lost due to infiltration. Therefore, the appearance of glazed pottery shows another great progress in pottery-making technology. In the middle and late Shang dynasty, glazed pottery gradually increased, indicating that people have developed from unconsciously discovering glaze to consciously preparing glaze. The analysis of glazed pottery unearthed in Shang and Zhou Dynasties proves that the glaze used at that time was lime glaze. That is, it is composed of carbonate such as limestone or calcite and a certain amount of clay.
People in ancient Egypt, Greece, India, Persia and other countries, like our ancestors, began to make pottery in the Neolithic age with hard work. Its development is somewhat similar to that of China, so I won't talk about it here.