In China porcelain made its debut in the period of Wei and Tsin and reached its zenith during the Sung dynasty. The porcelain industry of that time inherited the accomplishments of the Tang dynasty and Five dynasties, and developed even further. More important, manufacture skill reached new heights of excellence. Both official and private kilns developed. The most famous kilns are Ting Yao, Ju Yao, Kuan Yao, Ko Yao and Chun Yao. The most characteristic production is green porcelain known as 〝Celadon.〞 Ju Yao is famous for its celadon.The celadon of Ju Yao contained elements of pale green and pink.In terms of iridescence of the glaze and fineness of quality, Ju ware surpassed all other Yao wares. In the white porcelain class, Ting Yao is the leading kiln. Not only is the core of the products quite thin, but the glaze is very white, and the decorations are exceptionally fine. Kuan Yao ware is purely bluishgreen. Although its glaze is inferior to that of Ju Yao, the core of the products is the best. Ko Yao ware also belonged to the celadon group.All the ware from this kiln is dull white with a crackled glaze, considered one of the finest of its time. The colour of the glaze of Chun Yao is lustrous and pleasing. The Chun Yao is well-known for furnace transmutaiton (Yao-Pien).In the Sung period, Chun ware sometimes underwent transmutation to red or violet after oxidation, because of copper in the green pigment. These wares are called Yao-Pien. The masterpieces of the Sung dynasty featured on the stamps represent the earlist Chinese porcelain wares that have ever appeared on stamps as follows：
1.00 Fang Hu (vase), Ko ware： The vase is bronze shape with octagonal pear-shaped body, straight neck spread at the lip with two tubular handles and a high base. The vase is heavily potted and is glazed greyish blue and millet yellow in color. The entire surface of the vase is covered with dark crackles. The foot rim reveals a grey biscuit.
2.00 Fang Hu (vase), Kuan ware： This vase (Fang Hu) has a three-terraced body, glazed in light greenish-blue. The three terraced trapezoid body is narrower in the upper part and broader in the lower. It is straight neck, flat base, low foot, and thickly potted; the shade of the glaze appears light, 〝Eel's-blood〞 crackles intermingle with a few ice crackles on the surface. The footrim is unglazed, but coated with brown slip. On the base a poem by the Emperor Chiei-lung with two seals is inscribed.
2.50 Wan (Bowl), Ju ware： Lotus-flower shaped-bowl is glazed in light greenish-blue and shaped like a lotus-flower. The sides, deep, and narrowing towards the foot, are in the form of ten petals of a lotus-flower. The mouth is rather wide, the foot high and splayed, and the body thinly potted. The light greenish-blue glaze is uniformly smooth and luminous both inside and outside, with fine, close crackles on the surface. The mouthrim is tinged with high pink. Five spur-marks on the base reveal a yellow biscuit.
5.00 Lu (Incense burner), Kuan ware： Incense burner of bronze 〝Lien〞 form is with everted lip, flat base, and three short feet. There are three groups consist of three bands each in relief. Thick glaze is light greenish-blue and netted with ice crackles. The 12 spur-marks on the base show greyish black biscuit.
8.00 Lu (Incense burner), Chun ware： The incense burner has an everted mouth with projceting lip short neck, globular body and three feet. The burner is heavily potted. The glaze is light greyish blue in color with furnace transmutation of blue and purple spots. There are crackles on the surface of the vessel.The base of the feet reveals greyish biscuit.