NOW YOU KNOW

You can find it at the bottom of oceans and lakes, at the seashore and in deserts. What is it? Sand.

Most grains of sand were once parts of rocks or shells that crumbled. Waves pounding the shore and water freezing in crevices can speed up the process, called weathering.

Besides piling up to make beaches and low hills called dunes, sand has many uses. It’s mixed with cement to make concrete. And one type, called silica sand, is an important ingredient in glass.

Source: The World Book Encyclopedia

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