A millennium-old ceramic variety, which came to global attention when a shipwreck's cargo was salvaged, sheds light on a fascinating period of trade and art, report Wang Kaihao in Beijing and Feng Zhiwei in Changsha.

Conservator Yang Jinsong examines a ceramic bowl that is in need of restoration at Changsha Museum in Hunan province. (ZHU YOUFANG / CHINA DAILY)

High waves, a perilous, yet lucrative, voyage by a fully loaded cargo boat and an accident that seems too trivial to be documented in the long course of human history. These are the raw ingredients of an intriguing tale. A tale of treasure lost and found but also an insight into a creative era.

The Arabic-style sailing boat may have failed to deliver to the eager and expectant merchants waiting at its destination, most likely somewhere in the Middle East.

You can see how artisans and workshop owners in Changsha participated in a wave of globalization. They actively explored overseas markets and had a broad horizon.

Wang Lihua, director of Changsha Museum

No one can exactly say how the ship sank more than a millennium ago, but when the Batu Hitam ("black stone") shipwreck was found in 1998 off the coast of Indonesia, it stunned the world: Its well-sealed hoard offered a startling glimpse into the world of Chinese ceramics during the Tang Dynasty (618-907)－a cultural and social pinnacle during China's imperial era.

More than 67,000 Chinese ceramic artifacts were stored in its hold, and 50,000 of them seemed to originate from the same place, Changsha, the present-day capital of Hunan province. According to UNESCO, the cargo is the biggest single collection of Tang Dynasty artifacts found in one underwater location.

The so-called Changsha wares were produced in the kilns of Tongguan town on the outskirts of that commercial hub.

In the past four years, Yang Jinsong, a cultural relic conservator, has been devoted to breathing a second life into the broken shards at Changsha Museum. With his fingers, dozens of pieces of Changsha ware have been reassembled, allowing people to better understand the origin of these Tang treasures from the dust of history.

"A great deal of energy has been spent comparing these pieces and putting them back into their original positions," Yang says.

The biggest difficulty, Yang adds, is restoring the magnificence, splendor and luster to the colors and glaze.

Yang cleans the surface of a "Changsha ware" artifact. (ZHU YOUFANG / CHINA DAILY)

As one of the earliest known ceramic varieties in China to use under-glazed colors, Changsha ware is extremely demanding in its technique. One question has posed a challenge to every restorer: Since the original glaze is formed after being fired in a kiln, how can they re-create the appearance at room temperature?

Adding colors one layer after another requires patience and experience to create the right thickness of glaze to make the restored segments resemble the original.

A database is being gradually established based on archaeological discoveries of Changsha wares. Only digital analysis, scrutiny of earthen bodies, glazing materials, production techniques and other crucial information surrounding the ceramic samples, invisible to human eyes, can offer key references for restoration.

Despite the fact that modern technology may greatly facilitate Yang's job, he still feels like the artisan who first gave life to these exquisite pieces of porcelain.

After all, unlike bigger and national-level museums with much larger conservation squads and more detailed division of labor, only six full-time conservators work at Changsha Museum. Yang and his colleagues have to take care of the whole process, ranging from researching art history, performing chemical analysis, to actually fixing the artifacts.

Changsha wares from the Tang Dynasty, decorated with colorful images, are exhibited at Changsha Museum. (ZHU YOUFANG / CHINA DAILY)

"On average, fixing one ceramic artifact will take one month," Yang says. "But, if the situation is more complicated, more time is needed.

"Sometimes, you have to consider yourself a doctor," he says.

"A relic is your patient. Your duty is to cure it and prolong its life."

Nonetheless, an almost philosophical question was also raised by conservators: If the porcelain is a patient, should it be given a perfect appearance, just like in its prime?

According to Zhang Xingwei, director of the cultural relic conservation center at Changsha Museum, the basic principles of being "reversible" and "recognizable" are followed in restoration.

"If we figure out we've used the wrong materials, we need to be able to remove them," Zhang says. "Or if we find a better solution in the future, we have to be able to replace the traces of our current restoration."

In the gallery of Changsha Museum, some broken porcelain wares are also on display.

"Our mission is to maintain their health and keep them 'alive' as long as possible, rather than giving them an impeccable appearance," Zhang explains. "It's also a way to show people their past."

Students take notes while studying the Changsha wares that are showcased at the museum. (PHOTO PROVIDED TO CHINA DAILY)

Revealing a romantic age

Changsha wares have many stories to tell. Saturday is China's annual Cultural and Natural Heritage Day, and this provides a perfect opportunity to trace the origin of this ceramic.

According to museum director Wang Lihua, porcelain production first began in the late period of the Eastern Han Dynasty (25-220), but only in the middle of the 8th century did the golden age of Changsha wares emerge.

At that time, the chaotic An-Shi Rebellion severely hit North China, and many porcelain artisans fled southward, introducing their techniques and skills to today's Hunan region.

"Changsha's local flavor was then mixed in, and a new type of porcelain was born," Wang says. "The colorful wares in Changsha thus became a milestone of innovation in Chinese ceramic history."

At that time, white was the dominant color of porcelain production in North China, while celadons, or green pottery, was a signature product of East China, like present-day Zhejiang province.

"The rise of colorful Changsha wares was like adding the third leg of a tripod," Wang says.

But the products became famous for another reason. The romantic Changsha people added paintings or poems to the porcelain as decoration.

"There were even some advertisements, like for fine wines," Wang says. "These decorations, mixing painting and calligraphy, greatly enriched our understanding of ceramic cultures, and they also vividly reflect urban life at that time."

These ceramic artifacts, mainly daily-use items rather than art pieces merely for aristocrats to appreciate, can still radiate warmth and emotion.

Key items of Changsha pottery produced during the Tang Dynasty (618- 907) include (from left) a kettle featuring a poem; a ceramic lion; a decorated jar and kettle. They are all housed at Changsha Museum in Central China's Hunan province. (PHOTO PROVIDED TO CHINA DAILY)

"When you were born, I wasn't. When I was born, you were old. You resent I was born too late. But I regret you were born too early." This love poem would not be out of place on a messaging app. The words were actually written on a piece of Changsha porcelain that was unearthed in a 1983 archaeological excavation. It is now in Changsha Museum.

"Some stanzas on the wares are documented in history as famed poets' works, but most weren't," Wang says. "They were probably written by the artisans themselves.

"The Tang Dynasty was experiencing a cultural boom," he continues. "When the artistic and literary taste of society became more refined, many ordinary people could write poems. Changsha wares therefore recorded examples of folk literature."

More work is being done to seek physical clues indicating the prosperity of ceramic kilns in Changsha. Historical documents show that their production reached a peak in the early 9th century and declined after the 10th century.

According to Zhang Haijun, a researcher at Changsha Museum, archaeological discoveries of Changsha wares have occurred randomly over the decades, and key findings of kiln ruins have been made, particularly since 2010.

"The discovery of workshops, pits to bury broken ceramic, and other relevant industry heritage, has drawn a more complete picture of Changsha wares," he says. "We can better see how they were produced, distributed and marketed."

A colorful ceramic pillow. (PHOTO PROVIDED TO CHINA DAILY)

A far-reaching influence

In 2016, archaeologists excavated a site in Changsha which, throughout history, locals had called Fanjiaping. Remarks on a bowl salvaged from the Batu Hitam shipwreck also include the word Fanjia, probably indicating its production workshop.

The field research did not disappoint archaeologists. There were not only Tang Dynasty Changsha wares unearthed, but also some celadons from an even earlier period.

"They're key witnesses to the Maritime Silk Road and Sino-foreign exchanges of material cultures," Zhang Haijun says.

Batu Hitam was part of a trade network focusing on Chinese ceramics.

Archaeological findings show that Changsha wares were exported to about 30 countries, ranging from East and Southeast Asian neighbors to North Africa, according to Wang.

"You can see how artisans and workshop owners in Changsha participated in a wave of globalization," Wang says. "They actively explored overseas markets and had a broad horizon."

Consequently, to meet overseas demand, shapes of Changsha wares were also greatly influenced by exotic elements from beyond China.

For example, lion-shaped artifacts were found, as were a large number of examples featuring decorative patterns in typical South Asian, Persian and Arabic styles.

"These porcelain wares remind us of the importance of mutual exchange among civilizations in a modern context," Wang says.

So many remnants of these ancient odysseys may still lie deep under water. Though Changsha wares unveil a dynamic and booming epoch, full of entrepreneurship and pioneering spirit, for Yang, who has the privilege of viewing them daily, they bring inner peace.

"Everything in modern society seems to pursue a fast-paced lifestyle," he says.

"This work calms me down and enables me to savor artistic tastes throughout history. Seeing the artifacts, we can also understand the public aesthetics of their time. They tell what was viewed as traditional Chinese beauty."

Who knows? Changsha wares may be transient in a given timespan, but its legacy will be beneficial for many generations to come.

Zhu Youfang contributed to this story.

Contact the writers at wangkaihao@chinadaily.com.cn