Clay is a kind of cohesive soil, which contains less sand and is difficult for water to pass through, so it has good plasticity. It is an important mineral raw material. Is a very small particle (
Sand or sand making is a granular substance. Sand is a naturally formed subdivided rock with a size of 0.0625 to 2 mm. Individual particles in this range are called sand grains. In geology, the next smaller classification is mud, and its particle size ranges from 0.004 to 0.0625 mm.