Sand forms when rocks break down from weathering and eroding over thousands and even millions of years. Rocks take time to decompose, especially quartz (silica) and feldspar. ... Once they make it to the ocean, they further erode from the constant action of waves and tides.

Where does the ocean sand come from?

Most beaches get their sand from rocks on land. Over time, rain, ice, wind, heat, cold, and even plants and animals break rock into smaller pieces. This weathering may begin with large boulders that break into smaller rocks. Water running through cracks erodes the rock.

What is most beach sand made of?

The most common component of sand is silicon dioxide in the form of quartz. The Earth's landmasses are made up of rocks and minerals, including quartz, feldspar and mica.