* Rocks can be made of one, two, or several types of minerals.
* Minerals are elements or compounds of elements that occur in nature.
* Rocks are made up of minerals, but not all minerals are rocks.
* A mineral is pure, which means it is only made out of one type of molecule, and minerals have distinctive characteristics like color, hardness, and crystal structure.
There are three different types of rocks.
- Sedimentary
- Rounded-appearing mineral and rock particles that are cemented together
- Often in layers
- Igneous
- With or without observable crystals
- Not in layers
- With or without air holes
- Could be glass-like
- Metamorphic
- Crystals/minerals lined up (aligned)
- Often in layers, sheet-like
How are the different rocks formed? What are examples of each rock type?