Pumice is an example of extrusive igneous rock. The word extrusive means that the magma was forced onto the earth's surface and cooled in a matter of hours. Granite is an example of intrusive ...

That sculpted the rock, giving it the shape we can see today. ISLA: That’s right. It’s also an igneous intrusive feature, just like them. The rock they’re made of is called phonolite - also ...