Where Does Sand Come From? Unraveling Curious Facts On Sand Beaches

Joan Agie
Oct 12, 2023 By Joan Agie
Originally Published on Oct 22, 2021
Wide sandy beach on a tropical island
Age: 3-18
Read time: 5.8 Min

Have you gone to a beach recently and wondered where does sand come from?

Sandy beaches are a great tourist destination, where people can relax with family or friends. Taking a walk along the sandy coast can be an enjoyable, meditative experience for people of all ages.

Sand on beaches is not a result of one or two days of particles accumulating, it is the result of mountains and volcanoes deteriorating over thousands of years. Sand grains are the result of erosion of rock and mountains that settle down on seashores, forming beaches.

When mountains or volcanoes erupt and fracture, smaller pieces break off; these pieces roll down to become part of the river and the the ocean.

This process creates different colored sand grains found on various beaches around the world.

The color and shape of sand grains differ depending on where they are found, some are angular, blunt, or rounded. The shape of sand grains tells us about the long wear and tear journey it traveled before arriving as sand on beaches.

After you are done learning where does sand come from? You can also learn about where does silk come from? And where does water come from?

Do seashells turn into sand?

Sand is the main component of beaches. But sand found on beaches is not merely tiny particles of weak rocks and mountains. Though a large amount of sand is sediment and small pieces that have eroded from mountains and rocks, seashells similarly, are broken down into tiny pieces contributing to the formation of sand grains on beaches.

Seashells are found in the deep sea and come to the seashore by high altitude waves. Due to the high speed of the water when waves break, these shells are broken down into tiny pieces forming an element of beach sand. Another component of sand is parrotfish poop.

This, along with shell particles, form white crystal sand. With constant hits of water, they gradually become blunt. These shells witness an amazing and unknown world below the ocean surface of thick rocks and minerals.

Where does the sand on the beach come from?

Sand granules are the result of fast-moving rivers and water flowing into the ocean. When rivers move fast and combine with an ocean, they bring eroded particles of rocks with them. As water continues to flow, it pushes eroded particles of rocks, mountains, seashells, and even bone pieces of sea creatures, towards the seashore.

The journey of sand particles doesn’t stop there. Every time small waves hit the earth along the coast, they take the sand on beaches with them, whereas, heavy waves push it back onto the coastal regions.

When fast-moving water strikes rocks and the base of mountains continuously for thousands of years, it results in the erosion of rock and earth that ends up as sand granules in rivers and oceans.

There are several minerals and oxides found in ocean water, which can be partially attributed to the erosion of different types of rock. These oxides and minerals exist in the deep sea and come to shore with waves, giving beautiful pigments to beach sand.

Have you ever gone to Hawaii beaches? Hawaiian beaches contain beautiful black sand. Tiny sand granule sediments are brought to beaches from volcanic eruptions, which creates black sand.

Different colored sand granules on beaches are a result of calcium, from coral, iron oxides, minerals like black basalt, khaki feldspar, smoky white quartz, and green olivine. Interestingly, you will never see a beach with the same-colored sand granules.

Sand on beach and blue summer sky

What is beach sand made from?

Do you know the reason behind the tan color of sand along the coast? Tan sand is due to the presence of iron oxide.

Sandy beaches are made from different kinds of materials. The colors of sand granules on several beaches represent the materials and minerals they are made from. These beaches contain a vast variety of particles and materials, including cobbles, sand, shells, rocks, and pebbles.

Most of the beach sand is made from feldspar, which consists of the sediments of minerals and oxides present in ocean water. Feldspar and quartz make up most of the sand found on beaches.

Feldspar is formed from a combination of silica, sodium, potassium, and calcium. Similarly, quartz is also a result of the chemical structure of silicon dioxide.

The tan color of most sand on beaches is because of the large variety of quartz in its particles. Amongst the abundance of elements found in tan beach sand, sand granules can also be red in color.

The iron and iron oxides give the sand a red color. Black sand is made up of particles from coral and volcanic eruptions.

Furthermore, 80% of the white sand beaches are made from the poop of parrotfish. Parrotfish grind calcium carbonate reefs from coral and on excretion, the parrotfish excrete sand-like granules that are white in color.

Excretions from parrotfish are carried offshore, and eventually evolve into the white sand beaches found in Hawaii. Most of the sand granules stay in the ocean and form beds of water bodies, as well as a place for aquatic plants and seaweeds to grow.

As a natural resource, sand is quite often used in making glass, toothpaste, wine, food, paper, and plastic. Additionally, building sand or construction sand is usually mined from riverbeds. Pure white sand found in stores is usually chemically dyed. However, you can lighten sand by bleaching it under the sun for a couple of days.

How deep is the sand on a beach?

Sandy beaches are not formed overnight. After moving for millions of years, a part of these tiny particles is transported offshore.

After several thousand years of pushing and pulling by hard waves, they get sedimented to form sand on beaches. Their formation is the direct result of the deposition of rock and mountain pieces over several thousand years.

With time, the sand layer becomes thick, forming a landform with hundreds of meters of depth that we call beaches. These sandy beaches are found where the water is shallow and where the waves have less energy.

Beach landforms can be as deep as 328 ft (100 m) and as shallow as 32.8 ft (10 m). The age of the beach describes the depth of sand that is found offshore.

However, the depth of a beach can fluctuate, since the sand granules that deposit to offshore areas can remain there for long periods. As we mentioned, it takes thousands of years to form a beach.

Recently, authorities that have looked after beaches have found that sand is eroding from them. Because of this, they have been attempting to figure out ways to refill the eroding beaches with new sand.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestions for where does sand come from? Curious facts on sand beaches, then why not take a look at where does wax come from?

Does all wax come from bees? Or what are energy drinks? Where does taurine come from?

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Written by Joan Agie

Bachelor of Science specializing in Human Anatomy

Joan Agie picture

Joan AgieBachelor of Science specializing in Human Anatomy

With 3+ years of research and content writing experience across several niches, especially on education, technology, and business topics. Joan holds a Bachelor’s degree in Human Anatomy from the Federal University of Technology, Akure, Nigeria, and has worked as a researcher and writer for organizations across Nigeria, the US, the UK, and Germany. Joan enjoys meditation, watching movies, and learning new languages in her free time.

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