China has a long history of porcelain making. Blue and white porcelain, or Qinghuaci, designate white pottery and porcelain decorated under the glaze with a blue pigment, generally cobalt oxide. The decoration is commonly applied by hand, by stencilling or by transfer-printing, though other methods of application have also been used.
The first blue and white porcelains were as early as the ninth century in Henan province, China; although there were shards found there, the only three pieces of complete "Tang blue and white" in the world were recovered from Indonesian Belitung shipwreck in 213 and later sold to Singapore. In the early fourteenth century mass-production of fine, translucent, blue and white porcelain started at Jingdezhen, sometimes called the porcelain capital of China. Chinese blue and white porcelain was once-fired: after the porcelain body was dried, decorated with refined cobalt-blue pigment mixed with water and applied using a brush, coated with a clear glaze and fired at high temperature. Production of blue and white wares has continued at Jingdezhen to this day. Blue and white porcelain made at Jingdezhen probably reached the height of its technical excellence during the reign of the Kangxi emperor of the Qing Dynasty (reigned 1661 to 1722).
Baking blue-white porcelain originated in the Northern Song Dynasty (960-1127). During the Yuan and Ming dynasties (1271-1644), blue-white porcelain became increasingly popular, and since the 14th century, manufacturers have shipped blue-white porcelain to world markets. The porcelain reached its peak in the Qing Dynasty (1644-1911). Its thin, translucent quality and exotic motifs made it very valuable throughout Europe and the colonies, ranking first among blue-white porcelain nationwide.
Drawing the design with a cobalt pigment onto the stoneware body and painting over it with a transparent glaze creates the blue-white style, also known as "underglazed blue". The piece is then fired at a high temperature. Blue-white porcelain was introduced during the Yuan Dynasty (1271-1368) and has been in production ever since thanks to its bright colors, simple yet elegant patterns, and smooth glaze that never fades.
The Yuan Dynasty is a key period for the development of the firing techniques for blue-white porcelain in China. Its unique characteristics were based on the techniques of former dynasties. Blue-white porcelain had become a major porcelain product in China by the Ming (1368-1644) and Qing dynasties (1644-1911).
Blue-white porcelain of the Yuan Dynasty is large, with a thick roughcast. Generally, the works include big bottles, pots, bowls and plates, with the traditional flavor of the Tang (618-907) and Song (960-1279) dynasties. Due to the underdeveloped techniques, there are two interfaces on the body and several veins inside the body. The roughcast is not as smooth as that of the Ming and Qing dynasties and the glaze is thicker due to more iron in the raw glaze materials.
There are bamboo-like lines at the foot of the porcelain. The body is connected to the foot before the glaze is coated. The body is decorated with lotuses, clouds and flowers. Dense decorations were not only applied to blue-white porcelain but also to picture weaving and stone carving, reflecting the unique characteristics of the time.
The major producer of blue-white porcelain in the Yuan Dynasty was Jingdezhen. In addition, there were kilns for blue-white porcelain production in East China"s Zhejiang Province and Southwest China"s Yunnan Province .
Blue-white porcelain actually belongs to color-glazed porcelain and the coloring agent used is called cobalt oxide. First, using cobalt oxide, paint the unbaked mould, then apply a layer of translucent glaze over it and bake it at 1,300 degrees Celsius. The cobalt oxide will be reduced under the high temperature into a blue hue, which will be very bright and durable without poisonous lead. Each piece of monochrome-glazed porcelain has a single bright color with an exquisite design. A very good mastery of controlling temperature changes and content composition is required. Blue-white porcelain is most famous among the four traditional types of porcelain produced in Jiangdezhen, and is renowned as the "ever-lasting blue flower."
In 1979 Jingdezhen blue-white porcelain won a national golden prize and in 1985 it was honored with three gold medals at international fairs held in Leipzig, Brno, etc. Since then, the name "Jingdezhen Blue-white Porcelain" has spread far and wide. By far, it is a top product in the porcelain business, boasting the most prizes and highest standards.