Following its establishment, Goryeo allowed foreigners to enter the state including those from the Sung, the Khitan, the Jurchen and Japan, and encouraged foreign trade. Byeokrando, an international trade port situated at the mouth of the Yeseong River, served as the gateway to Gaegyeong. Here, merchants from the Sung, southeast Asia and Arabia engaged in trade. Goryeo became known as ‘Corea’by the Arabian merchants who engaged in active trade activities around the world. Byeokrando served as Goryeo’s window to the world.
Silk, herbal medicines, books and tea that the Chinese merchants brought were extremely popular with the aristocrats of Goryeo. Ivory, crystal, amber, spices such as pepper, quicksilver, and carpets brought by the merchants from Islam were also very popular. Goryeo, for its part, exported hemp cloth, ginseng, paper and ink sticks. The paper and ink sticks of Goryeo were of world-class quality.
Celadon ware of Goryeo was developed using techniques unique to Goryeo that integrated earthenware techniques of Silla, ceramics of Balhae and pottery of Sung China.
Celadon ware were sophisticated products widely used in people’s daily lives during the Goryeo period. Celadon ware were comprised not only of various vessels, but also incense burners, brush holders, rooting tiles, chairs, pillows and decorative tiles. Celadon ware were fashioned in such shapes as melons, bamboos, bamboo shoots, and gourds, combining art with nature. Celadon retains hot or cold temperatures for a long time. The feel of celadon on one’s lips is very soft. Celadon also enhances the flavor and taste of its contents. The custom of drinking tea accelerated the development of celadon ware. It was during the first half of the 12th century, when the aristocratic society thrived, that celadon production technology reached its height. Translucent jade-green pieces unique to Goryeo, as well as celadons with Sang-gam patterns of unique inlaid designs were produced. Sang-gam was a unique manufacturing method of carving patterns on the surface of the pieces, filling the area with clay rather than painting patterns on the surface with a brush. Popular patterns of Sang-gam celadon were clouds, cranes, as well as flowers such as chrysanthemum, apricot trees, peony and lotus. The celadon ware of Korea were world-class art, superior than those of China. In addition to the delicate jade-green celadon usually patronized by the aristocrats, the commoners widely used green celadon.