Longquan celadon, also known as greenware or celadon, is a type of green-glazed ceramic produced in China from approximately 950 to 1550.
Longquan is famous for its celadon pottery and the firing method that lends it an exclusive glaze. Most of the kilns were located in Lishui prefecture in southwestern Zhejiang Province in the south of China, and in Fujian Province to the north. It has been discovered as one of the largest historical ceramic production areas in China.
Celadon production at Longquan was long-standing, but it wasn't until the Northern Song period (960–1127) that large-scale production began, and when the capital was moved to Hangzhou, close to Longquan, after the start of the Southern Song (1127–1279) that quality and production continued to grow. The Yuan (1271–1368) and early Ming periods saw both quality and production stay at high levels. Celadons were an important part of Chinese exports for over five hundred years and were widely copied in other countries.
Typically made from violet-golden clay and a mixture of burned feldspar, limestone, quartz, and plant ash, the glaze is prepared using recipes that are often passed down for generations by teachers or within families. Glazes are applied to stoneware vessels, which are then refired six times in a repeating cycle of heating and cooling where precise temperatures are crucial. Over- or underfiring will ruin the effect. Celadon artists carefully monitor each stage with a thermometer and by observing the colour of the flame, which can reach temperatures of 1310 degrees Celcius. It comes in two varieties: older brother celadon has a black finish with a crackle effect; younger brother celadon has a thick, lavender-grey, and plum-green finish.
As in ancient China, jade is often used as a metaphor for virtues. The color of the glaze is low-profile with a jade-like gloss, which reflects the character of most Chinese — most are introverted. The glaze of Longquan celadon represents good virtues that the Chinese people have always cherished and pursued. The craft represents the heritage of the craftspeople, the country, and the city.
A large Longquan kiln cluster was formed in Jiangxi and Fujian due to the increasing popularity of Longquan celadon. Celadon wares from Longquan have been exhibited across the globe as representative works of Chinese porcelain, giving people outside China the chance to see the exquisite crafts of an ancient civilization. With its jade-like beauty and delicate craftsmanship, Longquan celadon now has become an integral part of the art collection of every country. Today, Celadon can be found in famous museums all over the world.
References
(https://ich.unesco.org/en/RL/traditional-firing-technology-of-longquan-celadon-00205) (https://en.wikipedia.org/wiki/Longquan_celadon#Markets_and_later_collecting) (http://www.chinatoday.com.cn/ctenglish/2018/cs/201804/t20180412_800126817.html)