Photo by Liu Xiao / Xinhua

"Some of the grottoes are not open to the public but we received photos of all the murals in the grottoes thanks to Duan's help," Jin says.

In 2011, the couple got the chance to reproduce Dunhuang murals in two caves on the Silk Road-themed street, a major challenge.

"Previously we painted the Dunhuang murals on canvas and paper, but this time we reproduced the entire mural on the wall. It would cost us a lot to fix if we made mistakes while painting on the wall," Yang says.

It also took a long time for the couple to prepare various kinds of pigments.

"The pigments used by ancient people were made from various ores and we had to also make pigments from these ores to make our paintings as close to the original colors of Dunhuang murals," Yang says.

Some people said the colors of murals by Yang and Jin were too bright, and lack a sense of history. But Jin explained that the colors of the original murals had faded with time.

The couple's hard work over two and a half years was rewarded with a payment of 1.5 million yuan from the project developer.

"We will continue our mural reproduction work with the money. Painting murals is the focus of our lives," Yang says.