38 Rocks and Minerals

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Rocks and Minerals by David Bauer With the Editors of TIME FOR KIDS

Chapter 1 In the Garden Let's go to the garden to plant seeds. Take a look at the soil. What do you see? Rocks! Earth is made of rocks and minerals. You can find them in the soil. Soil is a mixture of rocks, air, water, dead plants, and dead animals.

Chapter 2 Where Do Rocks and Soil Come From? Soil comes from rocks. Rocks come from Earth. Earth is a big ball of rock. Inside Earth, it is hot. The inner core is the center of Earth. The core is so hot that rock is melted there. During millions of years, the melted rock in the core pushes up. Some melted rocks cool and get hard just below the surface of Earth. This forms the shell of Earth, or crust. Sometimes the melted rock reaches the surface and cools. It forms hard rocks. Slowly, weather, water, and other things change big rocks into smaller rocks. These changes are happening all the time.

During winter, snow forms at the top of a mountain. In summer, the snow melts. It flows down the mountain. As the water flows, it breaks some of the mountain rock into pieces. The water turns into a stream. The water carries the rock pieces. The stream turns into a big river. The rock pieces get smaller and smaller. The river flows until it meets the ocean. Now the rock pieces are grains of sand.

Chapter 3 How Are Rocks Different? A rock is made of minerals. Granite is a type of rock. If you look at granite, you will see different colors in it. These colors are minerals. Minerals have many colors. Minerals have many shapes, too. Quartz is a mineral. It is a type of crystal. Calcite is another mineral. Calcite looks like frozen snowflakes.