Intrusive igneous rocks are the cool kids—no, literally, they cool down slowly underground. Picture a group of friends lingering after a party, taking their time to leave. That slow pace lets big, visible crystals form, like in granite.
Then you have extrusive igneous rocks, which are the impatient ones. They burst out of a volcano like a forgotten soda can shaken up in your car. Because they cool fast—sometimes in seconds—crystals don’t have time to grow. You get glassy obsidian or fluffy pumice that floats on water.
Ever dropped a piece of pumice in the bathtub? It’s like a rock that forgot it’s supposed to sink. It’s the comedian of the rock world—light, porous, and surprisingly useful for sanding your calluses.
