| A | B |
|---|
| core | Earth's center layer |
| crust | Earth's solid outer layer |
| fossil | Marks or remains of a once living thing |
| igneous rock | Rock that was once melted but has cooled 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 | Materials that settle into layers and harden |
| properties | Hardness, color, and shape are examples of a mineral's - |
| cast | What is formed when mud or minerals fill a mold? |
| pencils | Iron is used in ships, buildings, and cars but not these. |
