Joints are distributed widely in granite materials and affect the sawn goods performance of the rock. The beautiful sensation and the wear of rock_processed products are influenced by joints. Through the study of joints of different sizes in granite mass, it is known that joints not only control lumpiness of granite materials but also provide a good structural environment for weathering of the rock, causing the continuous development of weathering and the deeping of decoloration. The joints compose multiple patterns, and hence from numerous dark lines and spots on the polished surfaces of the rock, which reduce the average polishing glossiness and uniformity. Therefore , the study of joints of different sizes is an important link in the evaluation and exploitation of rock material resources.