Without the invention and development of fine porcelain, China's history would have been decidedly different, as the country's internationally known name suggests. The delicate chinaware it produced gained the giant oriental land worldwide fame as early as the 700s.

To preserve the time-honored industry and its birthplace, China is seeking to get a group of centuries-old kiln sites, where delicate chinaware was made centuries ago and where traces of the country's glorious past are still found today included on the United Nations Educational, Scientific and Cultural Organization's World Cultural Heritage List .

Among China's list of candidates to be submitted to the United Nations Educational, Scientific and Cultural Organization (UNESCO) are the three most widely known china kiln sites in the central province of Henan; namely, Ruyao kiln in Baofeng County, Junyao kiln in Yuzhou City and the Huangye tri-color pottery kiln in the city of Gongyi.

"All three are cultural heritage sites under top protection by the Chinese government, and they are ranked among the major archaeological finds in China in the 20th century," said Sun Xinmin, a China expert with the Henan Provincial Institute of Cultural Heritage and Archaeology.

"To a large extent, the world came to know China through the chinaware it produced and the country's porcelain was virtually used as a yardstick in evaluating Chinese civilization," Sun said.

Henan Province, one of the cradles of Chinese civilization, was at one time a production centre for chinaware, too, Sun said. "It was there that we found celadon glazed pottery made more than 3,600 years ago and the world's earliest white porcelain."

A writer of the Tang Dynasty (618-907) wrote in his book "The Classic of Tea" how the six largest kilns of the time produced celadon: a pale, soft, grayish green porcelain.

His description indicates that the Chinese porcelain artisans had already perfected their techniques. Contemporary researchers have corroborated the claims of the ancient classic, and state that China's porcelain production processes were perfected in the Tang and Song dynasties (960-1279).

But gone are the glories of the past. "They have all been lost through the passage of time: the craftsmanship and even the kilns are now mysteries of the remote past," said Sun.

Sun and his colleagues have over the past decades tried to find out the whereabouts of the ancient kiln sites, figure out their production processes and restore their original appearance. "We're duty-bound to do that, and to do it well," he said.

They confirmed in 1987 that Qingliangsi village in Baofeng County was the location of the 1,000-year-old Ruyao kiln, the largest celadon production site during the Song Dynasty. In 2000, archaeologists unearthed, in what they believe to be the ruins of the main processing section of the facility, 15 furnaces, two workshops, various instruments, a number of glazing materials and fragments of Ruyao porcelain pieces.

"They provided strong evidence on the official rank of the Ruyao kiln," Sun said.

Throughout China's history, celadon pieces made at Ruyao kiln were sent as tribute to the imperial court and were famous for their azure glaze blended with agate. But the unique technique used by the kiln artisans was lost during wars in the late Yuan Dynasty (1271-1368), and the site of the kiln remained a mystery to Chinese archaeologists until recent times.

Experts say that no more than 70 pieces from the Ruyao kiln still exist, all of them in museums around the world and valued at US$10 million each.

While celadon dominated the Tang Dynasty, chinaware became more colorful in the hands of artisans during the Northern Song Dynasty, who had learned to produce a unique red-tinged underglaze for porcelain with the red derived from copper.

In the early 12th century, an imperial kiln was set up to produce colorful porcelain pieces - mainly bowls, dishes, cooking vessels, vases and figurines - exclusively for the emperor and the imperial family. According to historical records, only 36 pieces were produced each year, none of which went into the collections outside the court.

Remains of the imperial kiln site known as "Junyao" were uncovered in Juntai village, in Yuzhou City, in 1974, and it was listed as the top archaeological find of the year.

To commemorate the development of the culture of chinaware, a museum has been erected on the ruins of the Junyao kiln and local artisans are working to revive the traditional craftsmanship by copying ancient pieces from the kiln.

Kiln ruins found in Gongyi City in 1957, made the site the first one discovered in the country that had produced the famous Tang Dynasty tri-color pottery, or tangsancai in Chinese.

In 2002, archaeological workers unearthed furnaces, workshops and a large number of tri-color pieces, half-finished pieces and various tools that revealed some of the manufacturing processes of the art.

"Ancient Tang tri-color pieces were all heated twice, before and after they were glazed," said Chang Jianchuan, director of the Henan Provincial Cultural Heritage Bureau.

Chang said they also unearthed remains of pieces of "Qinghua" porcelain, a type of ancient Chinese porcelain featuring blue-and-white designs, made in the Tang Dynasty. "The finding has settled a long-standing dispute about when Qinghua porcelain was first made," he added.

"By applying to be included on UNESCO's World Heritage List, we aim to remind local governments and people that our inexhaustible cultural heritage is the lifeline of the Chinese civilization and deserves to be protected well," said Chang.

He revealed a plan to build a museum on the ruins of the Ruyao kiln in the near future. "We've got the go-ahead from the State Administration of Cultural Heritage for the construction."

China is home to 29 World Cultural and Natural Heritage Sites, the third largest number in the world, following only Spain and Italy.

(China Daily June 26, 2004)