River pebble is a kind of pure natural stone, which is taken from the sand and stone mountains produced by the uplift of the ancient riverbed after the crustal movement thousands of years ago. It is subjected to the impact of mountain torrents and constant extrusion and friction during the transportation of flowing water. In the course of tens of thousands of years' vicissitudes, they suffered from the movement of waves and water, lost their irregular edges and corners by the collision and friction of gravel, and were buried in the ground with sediment for millions of years. The main chemical composition of river pebble is silicon dioxide. It is hard in quality, bright and simple in color. It has the characteristics of compression resistance, wear resistance and corrosion resistance. It is an ideal green building material. In the river pebble crushing process, the jaw crusher is mostly used for one breaking, and the cone crusher is used for two breaking and three breaking.