What Is Pumice, the Rock Full of Bubbles?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. What is pumice, the rock full of bubbles?

The Big Idea

Pumice is a rock so full of bubble holes that it is mostly air. It forms when frothy lava cools quickly and the gas bubbles get trapped. It is so light that it floats on water!

Frothy Lava

Step one: frothy lava. Some lava has lots of gas in it, so when it erupts, it froths up like a shaken soda. The bubbles fill it up, until it looks like foamy rock.

Quick Cooling

Step two: quick cooling. The frothy lava cools fast and hardens before the bubbles can escape. The empty bubble holes freeze in place, and they stay there forever.

Light as Air

Step three: light as air. Pumice is mostly air, so it is lighter than water and floats. Big rafts of pumice can drift across the ocean for years, carrying tiny sea creatures.

A Closer Look

Let's take a closer look! Look closely, and you see thousands of tiny bubble holes. Pumice is almost like a rock sponge. That makes it very light. Light enough to float on water. The bumpy surface can gently scrub rough skin.

Quick Facts

Quick facts! Few rocks float, so pumice is special. Pumice can be white, gray, or cream colored. People use small pumice stones to smooth rough skin. Never throw or hit rocks, because small chips can hurt eyes.

Think Like a Scientist

Now, think like a scientist! Fill a bowl with water. Put a pumice stone and a pebble of a similar size in it. Which one floats? Then look closely at the pumice with a magnifier.

Outro

Pumice floats because it is full of trapped bubbles. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!