Every member of First Emperor Qin Shihuang’s Terracotta Army—thousands of replicas of Chinese imperial guards rendered in clay around 221 BC—is unique and incredibly realistic, which is why they've fascinated researchers since they were discovered in 1974. Now, scientists in China say they’ve peeled back another layer of mystery—they've figured out the binding media used to paint the more than 8,000 soldiers, chariots, and horses, Science China Press announces. The army was covered with a couple layers of lacquer; layers of pigment and binding media went on top of this. The pigment was identified, but the binding media was a mystery, making it difficult to conserve or restore the figures—until now. By comparing "artificially aged" replica samples to the historical samples, researchers pinpointed the binding material as animal glue.
The Terracotta Army was built on the emperor's orders to guard the underground palace where he was buried, to protect him in the afterlife. Just as the palace mirrored the imperial capital, the warriors replicated the imperial guard. The intricately detailed statues were posed as if ready for a fight—and now they look set to join the ranks of movie superheroes, thanks to a planned collaboration between movie companies in the US, UK, and China, the Sunday Express reports. But the plot of the potential movie—which could end up being just the first in a new franchise—is probably not what the First Emperor envisioned. On the silver screen, rather than protecting the emperor, they’ll come alive to protect the modern world from aliens. The movie studios have some pretty awesome-sounding working titles, including Rise of the Terracotta Warriors and Super Terracotta Warriors. Move over, Spider-Man. (Another scientific mystery was recently solved using ... tree rings.)