Celadon, the Tripitaka Koreana and metal type

Jikji was printed with movable metal type in 1377, 78 years before Gutenberg's 42-line Bible.

Goryeo's wars and coups are only half its story. The same centuries produced three things that museums around the world still single out: celadon pottery with a blue-green glaze, a complete Buddhist canon carved on more than eighty thousand wooden blocks, and the oldest surviving book printed with movable metal type. Goryeo was also open to the world. Its capital Gaegyeong grew into a trading city, and envoys and merchants arrived at Byeollando, a port at the mouth of the Yeseong River.

Jade-coloured celadon

Goryeo potters learned celadon from China, from the Yue kilns in the south, and then made it their own. By the first half of the 12th century they were producing a clear blue-green glaze that Goryeo people called bisaek. In 1123 Xu Jing, an envoy from the Song, described Goryeo's celadon in his report on the country, the Gaoli tujing, noting that its workmanship and colour had become even finer in recent years. That remark matters because China was where celadon came from.

Goryeo then developed inlaid celadon, sanggam cheongja. The potter carved a design into the half-dry clay, filled the grooves with white or red clay, scraped the surface smooth, and then glazed and fired the piece, so the pattern showed through the glaze in white and black. The National Museum of Korea describes the two marks of Goryeo celadon at its height as the bisaek colour and fine inlay. The best workshops were at Gangjin and Buan. A famous example, the maebyeong vase with inlaid cranes and clouds, was made a national treasure in 1962 and is kept at the Kansong Art Museum.

The Tripitaka Koreana

The Buddhist canon carved during the Mongol war survives at Haeinsa temple in Hapcheon. The project ran from 1236 to 1251, and the blocks are dated 1237 to 1248 (Korea Heritage Service). Each block is about 70 centimetres wide, about 24 centimetres tall and 2.6 to 4 centimetres thick, carved on both sides, and weighs 3 to 4 kilograms. How many blocks are there? A count made in the colonial period gave 81,258, a number that includes blocks recarved in the Joseon period. In 2015, after a digital survey, the Cultural Heritage Administration announced 81,352. The blocks were listed in the Memory of the World register in 2007, and the halls that hold them, the Janggyeong Panjeon, became World Heritage in 1995.

Jikji and metal type

Goryeo also printed with metal type. A note written by Yi Gyu-bo says that 28 copies of a book of rites, the Sangjeong yemun (also called Sangjeong gogeum yemun), were printed with cast type. The note has no date; the Encyclopedia of Korean Culture places the printing between 1234 and 1241. No copy survives. The one that does survive is Jikji, a collection of Zen teachings compiled by the monk Baegun Gyeonghan (1298 to 1374; the Encyclopedia of Korean Culture gives his birth as 1299). His disciples printed it in the seventh month of 1377 at Heungdeoksa temple in Cheongju. Only the second volume is known today, and it is kept at the National Library of France. It became widely known in 1972 and was added to the Memory of the World register in 2001. In the same year 1377, Goryeo set up a gunpowder office under Choe Mu-seon, whose cannon would beat a pirate fleet at Jinpo in 1380.