Because the Song dynasty engraving has always been the oldest and most valuable, and the Song dynasty engraving is rarely passed down from generation to generation, it has always been treasured by collectors.
During the Ming and Qing Dynasties, the engraved version of the Song Dynasty was already worth thousands of dollars, and even the shadow version of the Song Dynasty was precious.
For example, Zhu's works of Song people are all carved in elegant fonts. Although we can't see the real thing, fortunately, the existing copies can also be treasured and hidden.