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