Transfer of sand between these areas does not represent sand loss. Sandy beaches tend to have more erosion due to wave action because they are less permeable to water and the larger backwash carries away as much sand as it delivers. The shape of the sand particles correlates with the permeability of the beach. Irregularly shaped particles can pack together more tightly, making a less permeable beach. Particles with regular shapes pack together leaving uniform pore spaces which serve to increase permeability.
Particle density affects the rate at which the particles settle onto the continental shelf.
The more dense the particle, the closer to shore it will be when it sinks to the bottom. The less dense particles can travel further from the shore before settling out. Sand is brought to the shore from the continental shelf, rivers and eroding cliffs, sand dunes, as well as from other beaches through the action of long shore currents. In addition, sand that is blown inland is also lost from the beach.