Moreover, since the rocks that contained the fossils were large, Lyu could only work in a basement or an outdoor shed where it was stuffy and damp in summer, and cold in winter. He used carving pens connected to air pumps as one of his main tools. But the pumps were noisy and the pens made a piercing sound and produced a lot of dust.

Lyu says he was encouraged by Tang Zhilu, an expert at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, when he met with difficulties during the fossil restoration.

"Tang told me to persist since it was my craftsmanship and willpower that were being tested, instead of my techniques."

Lyu says he feels a sense of satisfaction when the animals "come alive after being repaired".

After painstaking work, revealing the skulls or teeth of animal offers Lyu a sense of rebirth.

Lyu's first son was born last year just after he had finished restoring the Wangisuchus tzeyi fossils.

A graduate of the Shanxi Agricultural University, with a major in the management of agricultural and forestry economy, Lyu was recruited by the museum in 2012. He was initially bored while sitting there restoring fossils amid the noise and dust. But with time he began to feel a sense of achievement. He has already worked on restoring a large number of fossils.

He finds it worthwhile spending years on them since "fossils have been buried for millions of years or even more, but through my work, they can now be shown to the public".

Lyu says there are only about 200 people in the same profession around the country.

"Only a few people insist on doing this since it's quite monotonous, and you have to work in an undesirable environment.

"This job requires you to work by obeying the dictates of your conscience. You can do it carelessly, but given that it has been difficult for us to discover and dig out the fossils, you need to do the repair work as perfectly as you can."