Caveasphaera

So imagine you're playing with some play dough or clay. You can make any shape you want, right? Now imagine making a ball out of the play dough or clay that has a bunch of stuff inside it, like maybe some little beads or toys. That ball would be called a "caveasphaera."

In real life, caveasphaera are actually tiny balls made out of minerals that are found inside of rocks. Scientists study these caveasphaera to learn more about how the rocks formed and what they're made of. Basically, they're like a little mystery inside a rock that scientists can try to solve!