It is said that there are black gems in Chishui River. The story goes like this: A long time ago, there was a very poor village. Because the land is barren, crops can't grow. The villagers are very upset and don't know how to earn more money. There is a Chishui River near the village, which flows around the village. No one knows where its source is, where it flows, and how many years it has been like this. There is an old man with a long white beard in the village, who is the oldest person in the village. He often said that according to predecessors, Chishui River was formed by the tears she shed when she was in the Goddess Chang'e flying to the moon, and she left a necklace. Over the years, the necklace was scattered all over the floor and turned into a priceless gem with a black light.