Ru ware
[2] The shapes include dishes, probably used as brush-washers, cups, wine bottles (carafes in modern terms), small vases, and censers and incense-burners.
Their normal practice seems to have been to review the large quantities of "tributary ware" given to them by the provinces making ceramics, effectively as a form of tax.
The court kept what they wanted and redistributed the remainder as part of their lavish gifts to officials, temples, and foreign rulers, and perhaps also selling some.
[6] Production ended when, or shortly before, the kilns were occupied by the invaders who overthrew the Northern Song dynasty in the 1120s, but the wares remained famous and highly sought after.
Instead Ru ware was kept off the kiln stack surface by being supported on three or five small spurs or prongs, presumably of metal, which left little unglazed oval spots called "sesame seeds" on the underside.
[15] This "all-over" glazing technique seems to have been invented at the Ru kilns, and increased the resemblance of the wares to jade,[16] always the most prestigious material in Chinese art.
Another element in this resemblance was the "thick unctuous glaze texture", which has been described as "like lard dissolving not flowing",[17] The most admired type of jade was known as "mutton fat".
Although stoneware by Western criteria (not a category recognised in traditional Chinese thinking),[19] the wares are fired at a relatively low temperature, and are far from fully vitrified, absorbing water at a "fairly high" rate.
[20] Some authorities note that the body might really be considered earthenware, though it is always classified by Western writers as stoneware,[21] because of the other Northern Celadons it relates to, and in Chinese terms as "high-fired", usually translated as porcelain.
[23] A group of over 15 kilns at the village of Qingliangsi, Baofeng County, Henan have been identified as the site manufacturing Ru ware.
They were first identified in 1950,[24] and in 1977 the ceramic art historian Ye Zhemin found a sherd on the site which when analysed proved identical to a Ru ware sample in Beijing.
[29] In 2012 a Sotheby's catalogue note said "Although the exact time of the production of Ru ware is still under debate, all scholars agree that it was made for an extremely short period only.
[38] In the south a form of official Guan ware, more green than blue, seems to have acted as a rather inadequate substitute for the court.
This is a flat circular ring with an inscription claiming that it was the "first test piece", produced under the supervision of a "Vice-Minister of the Imperial Household" on 9 April 1107.
The Qianlong Emperor (r. 1736–95), a keen collector who must have owned at least half of the surviving examples, describes it in a poem "as rare as stars at dawn".
[42] A special favourite was a planter for daffodils without crackle, now in Taipei, where the undispersed holdings of the Imperial collection are today,[43] illustrated above.
[45] In 2012, Sotheby's identified 79 individual complete survivals,[46] and a revised list by Regina Krahl for Sotheby's next Ru sale in 2017 increased this to 87;[47] The National Palace Museum issued a list in 2015 totalling 90 pieces in various collections around the world, including some damaged in a fire in 1923; Krahl added and subtracted some pieces from this.
