Limestone

Do you know what a rock is? Limestone is a special kind of rock that is made by tiny creatures called calcium shells. These little animals lived long ago in the sea and when they died, their shells all piled up on the bottom of the ocean. Over time, the pressure from all the other shells and sand squished them together into limestone rock.

Now, limestone is really useful for all sorts of things! It's often used to make cement, which is what people use to build buildings and roads. You might have also seen limestone used for statues or fancy floors because it's really pretty when it's polished.

But limestone is also important for the environment. It helps to filter and purify water and it's even used in toothpaste! So, even though it started as a bunch of little creatures long ago, limestone is still really important today for lots of different reasons!