Archaeology: ‘Korean’ dish revealed as rare Imperial Chinese ‘Ru’ ware ceramic crafted 900 years ago

A blue–green dish held in the British Museum — long thought from Korea — has been shown to be one of less than 100 known pieces of the rarest type of Chinese pottery.

Dating back some 900 years to the time of Imperial China’s Song dynasty, ‘Ru official ware’ was noted for its lack of decoration and typically pale, ‘duck-egg’ blue glaze.

Produced only for a short period between 1086–1125 CE, Ru ware was produced exclusively for the use by members of the Northern Song Imperial court.

According to experts, the secret to Ru ware lay in its manufacture at the ‘Great Kiln’ of Qingliangsi, in Henan, which had access to clay of a particular composition. 

Since its introduction, there have been many failed efforts by potters to reproduce the special, ‘crackled’ glaze effect — particularly in the Korean ceramic tradition.

Like many of these efforts, the small, brush washer dish is not of the iconic blue most associated with Ru ware — although such did come in shades all the way to green.

It also sports relatively chunky spur marks (left by the supports in the kiln), quite unlike the tiny, seed-sized spurs commonly seen in Ru ware ceramics. 

For these reasons the item — believed genuine by collector Sir Percival David on acquiring it in 1928 — was dismissed as a Korean imitation around half-a-century ago.

However, fresh analysis by Far Eastern ceramics expert Regina Krahl suggested that the little dish was indeed a genuine Ru ware — prompting forensic chemical analysis.

Cranfield Forensic Institute experts performed non-destructive X-ray fluorescence analysis of the dish, comparing this with scans of real Ru ware and Korean imitations.

They found that the dish’s trace element ‘fingerprint’ matched those of the real thing— making the piece an unusual but nevertheless authentic piece of official Ru ware.

‘Regina Krahl’s experienced eye alerted us to re-examine the dish — which is smaller than an adult’s hand,’ said the British Museum’s Chinese ceramics curator Jessica Harrison-Hall.

‘When compared to other “Ru” wares in the collection, the cut of the foot ring, the shape of the brush washer and the ice-crackle within the glaze looked convincing.

‘But the colour of the glaze was quite grey and the marks on the base much larger than the usual sesame-seed shaped ones.

‘So. to be certain. the scientists were called in. They proved that she was right and another “Ru” ware existed. These are incredibly rare, beautiful and ancient — made just 20 years after the Battle of Hastings.’ 

‘It was a pleasure to be able to employ our analytical techniques on such important and rare examples of Chinese ceramics,’ added Cranfield Forensic Institute director and archaeologist Andrew Shortland.

‘There is great potential for art historians, curators and scientists to work together to confirm the attribution of important problem pieces.

‘I hope that this work will inspire further joint projects,’ he concluded.

‘We are thrilled that this imaginative collaboration between the Museum’s Chinese ceramics specialists and Cranfield’s forensic analysts has reconfirmed Sir Percival’s ground-breaking scholarship nearly 100 years on,’ said Sir Percival David Foundation chairman Colin Sheaf.

‘This enables our exceptional brush washer to rejoin the Foundation’s unequalled group of “Ru” wares.

These, he added, are ‘the greatest treasures within this unparalleled private collection now superbly displayed in its entirety at the British Museum.’