1 A rock hound is a person who collects rocks. Not only do they collect them, they can identify different rocks by studying their colors, textures, patterns, and hardness. Field guides and other books about rocks and minerals line their bookshelves. They own rock hammers, goggles, work gloves, and magnifying glasses. They have sturdy rock tumbling equipment to polish their finds, and some sort of container in which to display their rocks. It may be an old egg carton, or it may be a wooden display case with many different compartments. Every rock hound knows that rocks rule!
2 Rocks are made up of minerals. Some rocks are formed out of only one mineral, while others contain several different minerals. A mineral is a naturally occurring, solid substance that forms as a crystal. There are more than 4,000 different minerals, but of those only about 100 are common. Both diamonds and chalk are minerals. Since rocks are formed from single minerals as well as combinations of minerals, imagine how many different types of rocks exist!
3 Though rocks come in all shapes, sizes, colors, textures, and degrees of hardness, geologists can classify them in three main groups. These groups describe how the rocks were formed. This lesson will cover two of the three classifications. The third and most complex classification will be covered in Part 2.
