According to Song, academic writings on oracle bone inscriptions have been discovered in 14 different languages around the world, and the academic magazine run by his institution, keeps receiving papers with new angles from abroad.

"The statistics are insufficient though," Song tells China Daily. "When I did research at some of these institutions, I counted the pieces one by one, and found the numbers were more than their inventory showed, probably due to historical errors."

And, as he points out, there may be "thousands more" oracle bones in the hands of individuals in and around Anyang, Henan province, following discoveries there a century ago.

In the late 19th century, many oracle bones were unearthed by local villagers at the Yinxu Ruins in Anyang, an ancient capital during the Shang Dynasty. However, the locals regarded them as fossils and used them as ingredients in traditional Chinese medicine. There is a term used to describe this event as "humans swallowing Shang history".

Nevertheless, Wang Yirong, a Beijing scholar and antiquarian, stumbled on some animal bones and tortoise shells on sale at a pharmacy in 1899, and he noticed symbols that looked like writing. He was later hailed as the discoverer of oracle bone inscriptions.

People later swarmed to Anyang to dig for bones, and many fell into the hands of private collectors and antique dealers. In 1928, the government launched an official archaeological excavation at Yinxu and protected the area to prevent more artifacts from disappearing.

According to Zhao, most oracle bones housed in the National Library of China originated from these early 20th century private collections, which were either donated or purchased by public institutions.