Because in the society of the Tang Dynasty, the demand for folk kilns was too great, compared with the output of official kilns, it was amazing. (including foreign export trade), coupled with the strict restrictions of the imperial hierarchy at that time, compared with the official kiln, its quality requirements are very general. Its whole production and firing cost is incomparable to the official kiln tricolor. A large number of folk tricolor and folk kiln tricolor are comprehensively studied and analyzed. We draw the following conclusions: 1. The carcass of civil tricolor ware is much rougher than that of official kiln tricolor ware, which is because its tire-making technology is not very demanding, but that of official kiln is different. It is an official kiln tri-color manufacturing workshop specially set up by the Tang government. It is a funerary ware organization specially made for the royal family, meritorious service and other ministers. It selects the top artists with the best technology, rich experience and skilled operation from the folk kilns, organizes them and concentrates them in the official kilns to give full play to their great artistic talents. The whole process of making three-color official kiln in Tang Dynasty was completed under the strict supervision of Zhenguan official department. Therefore, the Tang government has strict requirements on the manufacturing technology of the three-color carcass of the official kiln. Never allow perfunctory, jerry-built, perfunctory behavior. Includes material selection, transportation, pottery training, staling, pulping, tire making, carving, blank tire, kiln baking, kiln discharging, air drying, glaze hanging, kiln baking and the like. Every subtle link is strictly supervised and managed by a special person. It can be described as meticulous. Compared with folk kilns, it has the characteristics of very pure, delicate and hard tire quality, generally too high firing temperature and strong corrosion resistance. The firing temperature of folk kiln tricolor ware is generally too low, and the firing temperature of its green body is mostly in the range of 800℃ to 1000℃, but the number that can reach 900℃ to 1000℃ is very small. People call this fetal quality. Powder tire This is because, in order to improve production efficiency and reduce the appearance of deformed defective products, it is the most practical and effective method to control the temperature between 800 degrees Celsius and 1000 degrees Celsius. The disadvantage of these folk kiln tricolor wares is that the unearthed tricolor wares are often seriously corroded in places where the soil has been buried for a long time and there are more saline and alkali, or under the condition of long-term flooding (such as the Yangtze River basin in the south of China). From a large number of unearthed objects, whether it is the whole object or the fragments, it is found that this phenomenon of corrosion and glaze removal is very serious. If it is such a three-color object, it is difficult to collect and preserve this three-color object. So it can be said that the corrosion resistance of folk kiln tricolor is still very poor. Buried tricolor wares are often well preserved because of their good geographical location, good soil quality, no saline-alkali components and water immersion. In fact, there are not many folk kiln tricolor wares that can be preserved without corrosion when unearthed. Therefore, in the past, many books written by experts in Guo Bo often said: True Tri-color didn't collapse and shed its glaze. This statement is extremely divorced from reality and is wrong. The reason is that what they often see are the three colors of folk kilns with good appearance and few survivals. And a large number of authentic tricolor unearthed in folk kilns are unheard of by those so-called famous artists.
Compared with the official kiln tricolor, the glaze color of the folk kiln tricolor is obviously thin and dark, without the thick and bright texture of the official kiln. This is because the glaze application of tricolor wares in folk kilns often follows the principle of proceeding from reality, reducing costs and improving energy efficiency as soon as possible. Therefore, its glaze quality requirements are essentially different from those of the official kiln tricolor. Official kiln tricolor requires strict quality, regardless of cost, the pursuit of luxury, the pursuit of high-quality and high-grade products. It is also very particular about glazing technology. Members of the royal family and hundreds of officials are also very particular when choosing cemeteries. The imperial court sent court geomantic officials to inspect the site and chose a satisfactory geomantic treasure house to build a cemetery. Whether it is the royal family or dignitaries, their requirements for the construction of cemeteries are also quite strict. From the earth, tombs, tombs, coffins, tomb walls, etc. The building materials used are all first class. Moreover, the technical requirements for tomb sealing are also very strict. Generally speaking, the tombs of the royal family and court officials are closed and the materials are carefully selected, so the Tang Sancai wares unearthed from these tombs are excellent in appearance, bright in glaze and as bright as new. Its glaze is rarely seriously corroded. Comparing the three colors unearthed in the coffins and tombs of ordinary people, we can clearly find that there are still great differences between them. Ordinary people's burial sites don't pay much attention to feng shui treasures, and the requirements for the construction level of tombs are also very simple. Not to mention the closeness of the pyramid-shaped mound. Not many, not even an epitaph. Most tombs are prone to leakage and collapse. In addition, the three-color lamps used are of low quality and few in quantity, and have not been corroded by salt, alkali and water. Coupled with the wanton destruction and trampling of grave robbers in past dynasties, there are only a few complete artifacts of Shangmin Kiln's tricolor.
The tire quality firing temperature of official kiln tricolor ware is generally too high, even if it is fired with red pottery tire soil, it is higher than that of private kiln. The three-color firing temperature of large official kilns unearthed in Gongyi, Zhengzhou, Xingyang and Beimangshan, Henan Province is relatively high. According to the local old man, this large and exquisite official kiln tri-color is called steel tire tri-color. The glazed surface of the official kiln tricolor ware is not only thick, but also has a strong glass texture, and its ability to resist saline-alkali erosion in soil is also very strong. Most of its works show the natural state of the combination of ice cracks and tiny snowflakes. Because of the thick glaze layer, the three-color ware in the official kiln rarely appears the phenomenon that the four sides of the piece are upturned. The folk kiln tricolor ware is different, because its firing temperature is low and its glaze is thin, so in the firing process, when its glaze is subjected to the expansion stress generated by the carcass, its opening becomes burst. This became the situation that the tricolor glaze was upturned widely circulated by experts in Guo Bo. Folk common names; Sesame chips. As for the glaze opening of tri-color in Tang Dynasty, we can realistically say that this is a common phenomenon of tri-color in folk kilns, but there is no such common phenomenon in large-scale real official kilns. The opening conditions of the official kiln tricolor are also inseparable from the most basic factor of stress expansion. However, if we insist that the glazed surface of tri-colored ware is upturned on all sides (sesame glaze), it will be the only criterion to identify the authentic tri-colored wares of Tang Dynasty, then this stupid one-sided view will inevitably lead to the danger that a group of truly rare national treasures-tri-colored wares of Tang Imperial Kiln will be killed at will. In that case, we will eventually become historical sinners!