A 16-piece set of jade belt ornaments was found in the same place. A lion appeared on all but one piece, each of which features the animal in a uniquely different posture. Although jade traditionally came from Hetian (also known as Khotan) in what is now Xinjiang Uygur autonomous region, by the Tang era it had long entered canonical Chinese culture.

Tang emperors routinely gave jade or jade-embedded gold belts to their high-level officials. The royal favor was bestowed not on mere whim but according to strict protocol that dictated, among other things, the specific pattern that would appear on the belt plaques.

"The combination of a 'foreign' motif with a typical Chinese carving material, as well as its incorporation into the court culture, all signaled an assimilation process that lay at the heart of the Silk Road exchanges," Li says.

Unearthed in Xinjiang and dating back to Tang is a clay rendition of the lion dance, widely performed during the lunar Chinese new year then and now. The two pairs of legs protruding from the underbelly of the lion indicate that there were two performers.

Compared with Han, the Tang Dynasty had remarkably more true-to-life portrayals of lions by artists and artisans, who, presumably, had more opportunity to observe the animal firsthand. Concrete details bristle where free imagination used to reign.