Scientists will coat the faces of the world-famous terra-cotta warriors in Xi'an with a microscopic-thin layer of chemical gel to protect the 2,000-year-old relics from mildew.
The warriors were unearthed in 1974 from the tomb of Emperor Qin Shihuang, said Zu Yong, director of the Nanometer Institute of the Northwest University.
Zu and his team of researchers have developed a transparent material that can absorb ultraviolet radiation, and thus preserve the original colors of the figures. It also can keep away bugs and bacteria, he noted.
The coating also helps improve the air quality, Zu said at an ongoing Trade Fair for Cooperation between Eastern and Western Chinese Provinces.
The nanometer membrane can also be used in silk and painting protection.
Wu Yongqi, director of the Shaanxi Provincial Museum of the Qin Shihuang Terra-cotta Warriors, said that finding effective means of preserving the warriors has long been a key issue for archaeologists. Little progress has been made in mildew prevention over the past two decades, though a breakthrough was made in the continuing excavation at the Qin Shihuang Tomb.
"China expects to fulfill the dream of maintaining the colors of the terra-cotta warriors forever with use of the nanometer technology," Wu said.
Dubbed "one of the eight wonders in the world," and the "most splendid archaeological find" in the 20th century, the Qin Shihuang Tomb was accidentally discovered in 1974 by a farmer digging a well. Since then, three huge pits have been discovered near the tomb.
Nearly 8,000 life-sized terra-cotta warriors and horses, along with tens of thousands of pieces of weaponry, have been uncovered from the three pits.
The ancient warriors and horses, located less than a mile from the emperor's tomb, were to protect the spirit of their ruler throughout eternity.
Most of the 1,000 unearthed warriors and horses from the tomb of the first man to unify China have lost their vivid colors. Researchers have learned that the lacquer on the warriors is highly sensitive to temperature changes, and the warriors suffered further from mildew and drying out when they were excavated.