Vase depicting a scholar in a garden

Blue-and-white Ceramics from China and Persia
One of the most important innovations by Chinese potters was that of underglaze painting, which involves applying iron-, copper-, cobalt-, and other mineral-containing pigments to the body of ceramics before glazing and firing. This method ingeniously prevents colorful designs from wearing out, and has had lasting effects on porcelain worldwide. Underglaze painted products of the Tang dynasty, some using imported cobalt (later known as blue-and-whites), joined the stream of Chinese trade with Southeast and West Asia. Unfortunately, a shortage of imported cobalt forced Chinese potters to use local cobalt, which produced a rather dull blue.

During the period of the Mongol domination of China, Persia, and Central Asia in the 1200s and 1300s, however, overland trade routes opened up, and Chinese potters were able to import high-quality cobalt from Central Asia more easily. Chinese potters were exposed to and greatly influenced by exotic designs on the underglaze-painted ceramics and the metal and glass artifacts that flowed in from the Persian world. Artisans at Jingdezhen, the center of porcelain production in southeastern China, revived the underglaze technique and produced porcelains with brilliantly painted decorations in imported cobalt. These wares then became popular and sought after in Persia and throughout the rest of Asia.