| A | B |
|---|
| core | center of Earth |
| mantle | middle layer of Earth |
| crust | outer layer of Earth |
| fossil | marks or remains of a once living thing |
| igneous rock | Was once melted but has cooled and hardened |
| sedimentary rock | materials that settle into layers and harden |
| metamorphic rock | rock that has been changed by heat and pressure |
| rock | solid material made of one or more minerals |
| minerals | solid natural object that has never been alive |
| rock cycle | a process of changing rock types |
