Most everyone has studied the Earth in some way. It can be as simple as picking up interesting rocks and wondering what kind they are. Take A Close-Up Look First, take a magnifying glass and look at each rock you have collected. You will see a lot of different particles. The different particles that form a rock are called minerals.
Minerals are the basic components that make up the Earth's crust.
There are hundreds of different types of minerals, but most rocks contain only a few types. You can try some simple tests to find out what type of minerals your rock contains. You can use some common objects to scratch a rock. For example, your fingernail is about hardness 2.5. If you can scratch a rock with your fingernail, then the rock must be less than hardness 2.5.