Sedimentary Rocks

Can we make rocks? Grab some sediment, like mud and sand, and you can make your own sedimentary rocks! You can even decorate them with things like shells and beach glass!

KAI: I like to make things and learn about things in my own way. I’m Kai and I’m a hacker.

And we can’t make quartzite either. Quartzite is a metamorphic or changed rock. Quartzite was once sandstone and over millions of years, temperature and pressure from sandstone into quartzite, but we don’t have lots of time or pressure or heat. We’re gonna make sedimentary rocks. Sedimentary rocks cover 75% of the earth’s surface, but only make up a small percentage of the earth’s crust compared to metamorphic and igneous types of rocks. Igneous rocks are made from cooling lava and magma. Sedimentary rocks are formed by sediment that is deposited over time. Usually it’s layers at the bottom of lakes and oceans. Things like limestone, mudstone, chalk, coal, and flint are all sedimentary rocks.

KAI: To make our rock, you’re gonna need a large mixing bowl, measuring cups, white glue, sand, and cornstarch, then whatever stuff you wanna add after to decorate your rock. To make the sand clay, we mix together two cups of sand, half a cup to one cup of corn starch, then add half a cup of glue. Add more glue if it’s too crumbly. Knead it like bannock until it’s smooth. And there you have it, sand clay. Now you can make shapes. You can decorate it. Let it dry, and you will have a homemade sedimentary rock. Homemade rocks!