Why do different beaches have different types if sand?

Wave action is the culprit

If a headland is being eroded, it will create a rocky beach

Also more powerful waves will deposit larger sediment, so some otherwise beaches will have rocks on the beach, and those rocks will be closest to the water, because heavier sediments will be deposited first, because the wave will lose energy as they slow down

beaches with just sand will have less powerful waves, so the the largest sediment that will be deposited will be grains of sand

Tidal flats have even less powerful waves, in fact there will be next to no waves there and the the largest sediment will be silt and mud

Of course, some beaches are artificial and all the sand is brought to them from elsewhere, or are naturally occurring beaches that are eroding too fast and much of that sand is also brought in from somewhere else and these beaches are often in overdeveloped areas.

Answer taken from answers.Yahoo.com User name Punk Rock and Minerals.