Dongba culture holds an important position in the life of Naxi people in Yunnan province. Traditionally, the Naxi people use Dongba paper as the carrier of their scriptures and paintings.

"Ink on Dongba paper won't fade over time. The paper can last for more than 1,000 years. Therefore, we Naxi people refer to it as immortal paper," said He Huaqiang, an inheritor of Dongba culture in Lijiang.

Unlike ordinary paper, Dongba paper is not smooth but feels rough and grainy. The paper has historically been made of the fibres of an indigenous plant called Wikstroemia. When you hold the paper against the light, you can clearly see the stems and leaves.

Why does the paper have such a long life? "Wikstroemia, the raw material for making Dongba paper, contains a special toxin. After processing, it is not harmful to humans but it deters the growth of borers and moulds," He explained.

Today, Dongba paper is still handmade according to the same process of more than 1,000 years ago. People collect Wikstroemia, peel off its black skin, and tear the white part into narrow strips. After cooking for two hours, the softened fibres are beaten until they resemble animal hairs. Next, they are put in a wooden trough and immersed in water, stirred by hand and eventually left to settle evenly at the bottom. Later the trough gets taken out of the water in order to get the paper from the bottom. Finally, the paper is sun-dried and repeatedly pressed, and made into a sheet of Dongba paper.