Pebbles as a pure natural stone, its formation is the cause of the broken rock, the long time of the water brush angular disappeared, forming a round or oval stones (or pebbles, Li Shi). The main ingredient is SiO2 followed by a small amount of iron oxide and trace amounts of iron, copper, aluminum, magnesium and other elements and compounds. The unjust these pigment particles dissolve in SiO2 hydrothermal type and content, thus showing a depth of shade, the changing color, the pebbles showing a black, white, yellow, red, green, green color.
The pebbles in the water treatment, commonly used as a supporting layer, play a supporting role, also known as gravel bearing material. I produced pebbles, washed, screened and into. Its appearance is oval, better than the surface area, high mechanical strength, no impurities.