C4120 Layers of Vigilance

The handwriting mimicry looked simple, but it was very difficult to make. The ancient literati had done a lot of research on the anti-forgery of signatures!

If the forger didn't know the location of the needle, then even if he could imitate it, he would still be able to find out that it was fake!

Wealthy scholars would mix the ink with very fine cinnabar or gold chips