The leader of porcelain, the sky-blue glaze after the rain—Ru Ware.

Ru porcelain, also known as Ru Kiln, Ru Ware or Ru Ceramic, is famous for its production of celadon porcelain, using precious agate as glaze, with the most precious glaze color being "The sky turns blue after rain  and the clouds break". Ru porcelain was originally a civilian kiln, but during the late Northern Song Dynasty when Emperor Zhenzong of the Song Dynasty ruled, "since the white porcelain from Dingzhou had spikes and was unsuitable for use, he ordered the construction of a green kiln in Ruizhou", so Ru porcelain began to produce imperial ceramics for the palace.

After the fall of the Song Dynasty, Ru porcelain also disappeared, so the time span was only about 20 years. The Ru porcelain ceramics produced for the palace during this 20-year period are called "Ru ceramics", which is a specific term, referring to the Ru porcelain of the Five Famous Kilns. Because the production time was extremely short and the surviving items are rare, only about 67 items are recorded in the national archives, so it is extremely precious.

Among 67 surviving pieces, 23 pieces are housed in the National Palace Museum in Taipei, 17 pieces in the Palace Museum in Beijing, 8 pieces in the Shanghai Museum, 7 pieces in the Percival David Foundation of Chinese Art in the UK, and the remaining pieces are scattered across various museums and private collections in the United States, Japan, and other locations, totaling around 10 pieces.

Northern Song Dynasty Ru Ware Sky Blue Glazed Brush Washer

With a diameter of 13.5 cm, this exquisitely crafted piece was used by ancient scholars for washing brushes. It was originally part of the collection of Adolf de Rothschild and later transferred to a private Japanese collector.

In April 2012, it was auctioned at Sotheby's Hong Kong for $26.8 million (equivalent to HKD 279 million), setting a new world auction record for Song Dynasty ceramics.

Mordern Ru Porcelain

The development of modern Ru Porcelain has reached the level of ancient Ru ware, but this level is not simply a technical replica. Instead, it has inherited traditional techniques while injecting modern design and innovation. Modern Ru ware has continuously improved and innovated traditional techniques by introducing new materials, adopting new techniques and kilns, etc., and has reached a height of modern pottery.