The pebbles that are to be found on a beach are invariably round and smooth owing to the constant battering they have received from the sea.
Originally pebbles were part of much larger rocks, but various natural phenomena such as earth-quakes and volcanoes, have gradually broken them down. Caught in the movement of the sea, and constantly rubbed against other hard materials, the pebbles finally lose their irregularities and present a smooth round surface.
Many of the rocks of today will be pebbles in thousands of years time, and many of today’s pebbles will eventually be turned into sand by the constant, wearing action of the sea.
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