Textbook P 148
Granite is not easy to be weathered, and its appearance color can be maintained for more than 100 years, so outdoor floors, walls, cylinders, footholds, grass-roots and steps often use coarse-grained and fine-grained plates; Mirror panels are mainly used for indoor and outdoor floors, walls, cylinders, countertops, steps and so on. , especially suitable for floors of large public buildings.