Rocks (Book)

This chapter discusses the rock cycle and each of the three major types of rocks that form on Earth. Separate sections cover igneous, sedimentary, and metamorphic rocks individually.

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Most of the Earth is made of igneous rock. The entire mantle is igneous rock, as are some areas of the crust. One of the most common igneous rocks is granite (Figure).

Many mountain ranges are made of granite. People use granite for countertops, buildings, monuments and statues.

Pumice is also an igneous rock. Perhaps you have used a pumice stone to smooth your skin. Pumice stones are put into giant washing machines with new jeans and tumbled around. The result is stone-washed jeans!

Image of life-size elephant is carved from granite

This life-size elephant is carved from granite.


SCI-MS.ESS2.01 Develop a model to describe the cycling of Earth’s materials and the flow of energy that drives this process.


Lesson Objectives

  • Describe how igneous rocks are formed.
  • Describe the properties of some common types of igneous rocks.
  • Relate some common uses of igneous rocks.