The color of porcelain is closely related to the mineral components contained in the body or glaze. The same mineral components can also change into different colors depending on their content. Pottery is usually fired with clay containing iron oxide. Depending on the firing temperature and degree of oxidation, the colors range from yellow, reddish brown, brown, gray and other colors. Adding other mineral components to the clay can also be fired into other colors, but this is less common. Porcelain has always been rich in color and variety, and its brief introduction is as follows:
(l) Celadon: Porcelain with cyan high-temperature glaze. The main coloring substance in celadon glaze is iron oxide, with a content of about 2%. Depending on the content of iron oxide, the thickness of the glaze layer and the degree of reduction of iron oxide, glaze will show colors of different shades and tones. If the iron oxide in the glaze is reduced to ferrous oxide, the glaze color will be greener, otherwise it will be yellower, which is related to the firing atmosphere. The firing atmosphere refers to the flame properties when baking ceramics, which are divided into three types: oxidizing flame, reducing flame and neutral flame. The oxidizing flame refers to the flame in which the fuel is fully burned to produce carbon dioxide; the reducing flame refers to the flame in which the fuel is burned in the process of lack of oxygen, producing a large amount of carbon monoxide, carbon dioxide, hydrocarbon, etc.; the neutral flame is somewhere in between. When fired with an oxidizing flame, the glaze will turn yellow; when fired with a reducing flame, the glaze will turn green. Celadon is often decorated with "splits". The so-called splits are cracks in the glaze layer of the porcelain due to the different expansion coefficients of the body and glaze. The surface of the work handed down from Ge Kiln is a combination of large and small pieces. The small pieces are yellow and the large ones are black, so they are called "gold iron wire". The official kilns of the Southern Song Dynasty made the best use of the characteristics of open slices, thin bodies (gray, black), and rich glazes (pink blue, fire yellow, cyan gray, etc.). The edge of the utensils is slightly exposed due to glaze sagging, and the bottom of the utensils is The foot is exposed due to the burning of the cake pad, so it is called "Purple Mouth Iron Foot", which is considered expensive. Yue kiln is world-famous for its celadon production. Its works show a special "sunny after rain" color and texture like ice and jade. They later spread abroad and became representative works of Chinese porcelain.
(2) Black porcelain: Porcelain with black high-temperature glaze. The iron oxide content in the glaze is above 5%. Primitive black porcelain appeared during the Shang and Zhou dynasties. During the Eastern Han Dynasty, the black porcelain fired at the Shangyu Kiln was glazed with even thickness and thickness, and the glaze colors were black, dark brown, etc. In the Song Dynasty, a large number of black glaze varieties appeared. Among them, tea bowls with rabbit hair patterns, oil drop patterns, and obsidian patterns were fired in the kiln because the iron content in the glaze was high, the kiln was kept warm for a long time, and they were fired in a reducing flame. A large number of iron oxide crystals precipitated in the glaze. , the finished product shows a special pattern of brilliance. Each piece is unique when you look closely. It is a rare and precious tea set.
(3) White porcelain: white porcelain with transparent or opalescent high-temperature glaze. In long-term practice, the potters have further mastered the law of discoloration of porcelain, so on the basis of firing celadon, they reduce the content of iron oxide in the glaze and use an oxidizing flame to bake it. The glaze color is generally white with yellow or green. The glaze color is bluish when fired with a reduction flame, and is known as "blue and white porcelain" and "shadow blue". The production of white porcelain was very developed in the Tang Dynasty. The Xing kiln in the north was the first to excel in its craftsmanship. The white porcelain fired was as silver as snow. For a time, it was as famous as the Yue kiln in the south that produced celadon. It was known as "Southern Qing and North White".
(4) Color glazed porcelain: a general term for various types of high-temperature glazed porcelain with a single color. The main colorants include iron oxide, copper oxide, diamond oxide, etc. Using iron oxide as colorant include celadon glaze, black glaze, sauce glaze, yellow glaze, etc. Using copper oxide as colorant include crabapple red glaze, rose purple glaze, bright red glaze, stone red glaze, red glaze, cowpea red glaze, etc., all of which are fired with reducing flame. If fired with oxidizing flame, the glaze will be green. Porcelain with cobalt oxide as a colorant turns into different shades of blue after firing. In addition, the yellow-green iron-containing crystal glaze color is also a color glaze porcelain, commonly known as "tea powder".
(5) Colored porcelain: a general term for underglaze and overglaze porcelain. Underglaze porcelain is made by first decorating the base with colored materials, then applying cyan, yellow or colorless transparent glaze, and firing it at high temperature. Overglaze colored porcelain is made by drawing patterns on the fired porcelain with various colors and then baking it at low temperature.
(6) Blue and white: one of the varieties of underglaze color, also known as "white glaze blue and white". The white green body is painted with cobalt oxide-containing pigments to create patterns, a transparent glaze is applied on the outside, and it is fired at high temperature.
When firing, the blue and white are dark in color when using an oxidizing flame, and bright in color when using a reducing flame.
(7) Underglaze red: one of the varieties of underglaze color. Patterns are drawn on the porcelain green body with pigments containing copper oxide, then transparent glaze is applied, and the porcelain is fired at high temperature with a reducing flame.
(8) Doucai: A variety that combines underglaze blue and white with overglaze color, also known as "doucai". First, use blue and white materials to draw an outline image of the pattern on the porcelain green body, apply a transparent glaze and bake it at high temperature. Then fill in the outline image with red, yellow, green, purple and other colors, and then use low temperature Baked. In addition to color filling, there are also several types such as stippling, adding color, and dyeing.
(9) Five colors: one of the varieties of overglaze colors, also known as "hard colors". It is made by painting patterns on fired white porcelain with various colored pigments such as red, green, yellow, and purple, and then baking it at low temperature.
(10) Pastel: one of the varieties of overglaze color, also known as "soft color". It is made by using "glass white" containing arsenic oxide as a base on the fired bisque, then using various colored pigments to render the painting, and baking it at low temperature.
(11) Enamel: One of the varieties of overglaze color, also known as "porcelain body painting enamel", that is, painting on fired white porcelain with enamel material. The main components of enamel are borate and silicate, mixed with different metal oxides, and after low-humidity baking, it takes on various colors, mostly with yellow, green, red, blue, purple and other colors as the base. Then, various patterns of flowers, birds, landscapes, bamboos and stones are painted to give the pattern a raised feel.