The defination of pebble can be described as a rock with a specific size around 4 to 64 mm. Pebsbles are considered to be larger than granules and considered smaller than cobbles. A rock made predominantly of pebbles is termed a conglomerate.
Our River Pebbles come in a variety of colors and they can have streaks of quartz and different colored rock. Pebbles are mostly smooth but, dependent on how frequently they come in contact with the sea, they can have marks of contact with other rocks or pebbles. Pebbles left above the high water mark, may have the growth of organisms such as lichen on them, signifying the lack of contact with sea water.