1. Chapter 3
Rocks

2. Rocks
Any solid mass of mineral or mineral-like matter that occurs naturally
Most rocks are MIXTURES of minerals
Some rocks contain nonmineral material (shells, plants, bones, etc.)
Some rocks do not have crystalline structures

3. Classification of rocks
Rocks are classified based on how they were formed.
Three classifications
Igneous – form when magma or lava cools and hardens
Sedimentary – form when sediments are compacted and cemented
Metamorphic – form when rocks are changed by extreme heat and pressure

4. Rock cycle Shows relationships between different rock forms
All rocks can be changed from one kind to another
Ex. Igneous rocks can become sedimentary rocks through weathering and erosion
The Rock Cycle shows how these changes can take place.

5. Rock cycle