| A | B |
|---|
| sedimentary rock | rocks formed by compressed layers |
| igneous rock | rocks formed by molten lava that has cooled |
| metamorphic rock | rocks that have been changed by heat, pressure, or both |
| fossil | any remains or trace of an organism that are at least 10,000 years old |
| mineral | a substance occuring in nature that is neither plant nor animal |
| amber | hardened tree sap if which fossilized insects are often found |
| cast | a fossil that has formed inside a mold |
| imprint | a fossil created by an imprint |
| mold | a hollow fossil form that clearly shows what the outside of the organism looks like |
| relative age | a comparison that between two things that helps tell how old something is |
| luster | how light bounces off a mineral |
| streak test | the color left behind when a mineral is rubbed on a streak plate |
| hardness | a property that tells how easily a mineral can be scratched |
