Three excavations

In 1974, the Terracotta Warriors were found by villagers in Xi'an's Lintong district.

The figures, commissioned by Emperor Qin, have undergone three archaeological excavations, with the first spanning more than six years.

The second took place in 1985 but was suddenly halted, as there were only limited ways to protect the colorful painting on the figures at the time.

The most recent excavation started in 2009, when the National Cultural Heritage Administration approved the resumption of work in a section of the No 1 pit.

Lan, the conservator-restorer, was one of those responsible for the resumption, which marked a turning point in his career.

Before this, he had only repaired one or two Terracotta Warriors every year, treating the relics with the greatest care and displaying infinite patience.

However, since the excavation resumed, he has restored pottery shards from more than 150 figures and has gradually come to know the differences between each one.

"The Terracotta Warriors feature colorful painting and even the fingerprints of the craftsmen who made them. The artisans' names are also etched on them, but they can be hard to find," Lan said.

"If you look closely at the pottery shards, you can see traces of the artisans' fingerprints and complete palm prints left after they vigorously slapped the clay. There are also traces of the hairs they shed," Lan said.

All these traces are well-preserved, he added.

Using his experience, Lan can tell precisely whether the Terracotta Warriors were made by craftsmen from the Qin Court or by local artisans, as their work is quite different.