sand particles are bigger in size than clay particles
sand_particle is not particle. sand_particle is particle. sand is group_of_sand_particles. group_of_sand_particles is not group_of_particles. sand is not group_of_sand_particles. sand_particle is not stone. sand_particle is stone. group_of_sand_particles is group_of_particles. sand is not very_small_rocks. sand is very_small_rocks.