Is Zhang Hui's black soil series collectible?

Zhang Hui's black soil series is very collectible. Zhang Hui is a famous photographer in China. His series of black soil works show the natural scenery of black soil in northern China and the emotional world of farmers' life in the form of black and white photography, which has high historical, cultural and artistic value. These works are widely displayed and collected, and regarded as treasures in the history of photography in China.