Introduction to the chessboard stone: The chessboard stone is a granite body that is 0.8-120 million years old. The rock that forms the chessboard is a fine-crystalline dike. During the cooling process of the dike, mutually perpendicular joints are formed. These joints cut the dike into small squares. Later geological movements caused the rocks to roll down the hillside, and the rocks cracked along the cracks, forming a vivid checkerboard stone.