Sand

Water is the main medium that causes the rock weathering in rivers, it transports and transforms the sediments that are in its path. These sediments can be carried by surface and subsurface runoff, provoking different dispositions and shapes in the sediments.

Also, there are different factors that influent in size and arrangement of sediments, like water velocity during the river course or the land inclination. Through the thawing process of a sphere we can appreciate how water moves sand particles, creating a random composition different from the original.