Bentonite facts for kids

Bentonite is a special type of clay. It forms when volcanic ash changes over time. Imagine tiny bits of ash from a volcano mixing with water and getting squished under pressure. That's how bentonite is made!

This clay can hold a lot of water. Different kinds of bentonite have different amounts of things like sodium, calcium, or potassium. Because it can soak up so much water, bentonite is used in many ways, like making things thicker or helping them slide smoothly.

What is Bentonite?

Bentonite is a natural clay that forms from weathered volcanic ash. This means that over a very long time, tiny pieces of ash from volcanoes break down and change. When this ash mixes with water and is under pressure, it turns into bentonite clay.

How Does Bentonite Form?

Bentonite clay usually forms when volcanic ash settles in water, like in a lake or ocean. Over millions of years, this ash slowly changes into clay. This process is called weathering. The ash reacts with the water and other minerals, creating the unique properties of bentonite.

What Are the Different Kinds of Bentonite?

There are different types of bentonite, depending on what minerals are most common in them. The main types are:

• Sodium bentonite: This type can absorb a lot of water and swell up a lot. It's often used when you need something to expand.
• Calcium bentonite: This type doesn't swell as much as sodium bentonite. It's good for absorbing oils and other liquids.
• Potassium bentonite: This type is less common. It forms when volcanic ash changes in a different way.

What is Bentonite Used For?

Bentonite clay is very useful in many different industries. Its ability to absorb water and swell, or to act as a lubricant, makes it valuable.

• Drilling mud: It's used to make "drilling mud" that helps cool and lubricate drill bits when digging for oil or water.
• Cat litter: Many types of clumping cat litter use bentonite because it absorbs moisture and odors well.
• Cosmetics: It's found in some face masks and other beauty products because it can absorb oils from the skin.
• Medicine: Some people use it as a medicinal clay for various purposes, like soothing skin.
• Building: It can be used to seal ponds or landfills because it forms a strong, waterproof barrier.
• Wine making: It helps to clarify wine by removing unwanted particles.

Images for kids

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  Bentonite layers from an ancient deposit of weathered volcanic ash tuff in Wyoming

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  Gray shale and bentonites (Benton Shale; Colorado Springs, Colorado)

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  Creating a bentonite slurry for fining after wine pressing

See also

In Spanish: Bentonita para niños