字幕表 動画を再生する 英語字幕をプリント Hi there! You're just in time! Squeaks and I are hoping to discover some amazing things today! We have three rocks that we think are geodes! Have you ever seen one? Geodes are rocks that look like regular rocks on the outside, but inside they're filled with beautiful crystals! Finding one is exciting because it can take geodes thousands or even millions of years to form. They start out as rocks that form with empty spaces in them. Sometimes there's an empty space because of bubbles of gas inside the rock, especially if the rock comes from a volcano. Other times, there used to be something like a tree root inside the rock, but it broke down over time and left an opening in the rock. Then, water from rain or rivers can get into that empty space, and over time, the water leaves behind minerals. A mineral is a kind of natural material that isn't alive — like a crystal! There are tiny bits of minerals in water, and those little pieces get left behind as water flows through the empty space in the rock. And if that happens enough over a very long time, the minerals start to build onto each other and form crystals. So the bigger the crystals inside a geode, the older the geode is. Our geodes look pretty small, so if there are crystals in them, they're probably small. What do you think, Squeaks? You're right, there's only one way to find out! Let's break these open! If you want to try this at home, you can collect geodes from certain places where there are lots of them, called geode beds. Or you can buy special kits with geodes in them Once you have your geodes, make sure you have a grownup to help you break them open. You'll need a sock, a hammer, safety glasses or goggles, and a safe place to break open your geodes. Squeaks and I are going to go outside and break ours open on the sidewalk. Be patient with this part if you're doing it at home. Because it might take a little while. Ready, Squeaks? Let's go outside. First, put on your safety glasses. We're going to leave ours like this so you can see it break open You'll want to hit the geode with the pointed back part of the hammer so that you break the rock in half instead of just smashing it to bits. It might take a few small hits. There it goes! Is it a geode? Ooh look there they are! You can see the crystals inside have formed Let's smash the other ones and see what's inside! These have bigger crystals, so this geode must have been able to collect minerals longer than the other ones. Alright let's try this last one I'm going to use the flat side of the hammer and see what happens Oh man, it smashed it to bits! So if you're going to use the flat side, be careful Where should we put our pretty new geodes, Squeaks? Yeah, good idea. They look good there. Thanks for learning about geodes with us! We want to also thank Google Making Science for helping us make this video about these awesome rock formations. If you break open your own geodes, send us a picture at firstname.lastname@example.org Thanks and we'll see you next time. Here at the fort!