What is a Rock? Coal made from the remains of living organisms A rock is not a mineral. It is composed of one or more minerals and sometimes contains organic material. Coal is considered a rock. What is the difference between rocks and minerals? A mineral, by definition, must meet four criteria. It must be a naturally occurring, solid substance that has an internal crystal structure and is formed by inorganic processes. Rocks are made up of minerals. How Do Minerals Form? Minerals form in a variety of geologic environments. Some form as a result of intense heat and pressure created during metamorphism. Some minerals form from hot-water solutions created when ground water is heated by magma. Other minerals form from liquid rock as it cools. Yet another group of minerals form as ocean water evaporates. Minerals 1 - naturally occurring 2 - inorganic (nonliving) 3 - solid substance 4 - crystal structure Rocks are solid, naturally occurring substances composed of one or more minerals and other matter. Rocks are classified into three groups according to how they were formed. Igneous rocks form when liquid rock cools and hardens. Liquid rock that is under the crust is called magma. When it pours out onto the Earth’s surface, it is then called lava. Metamorphic rocks are rocks that have changed as the result of intense heat and pressure deep in the Earth’s crust. Sedimentary rocks are rocks that have been placed in layers by weathering or erosion. Over millions of years, these layers are compressed and cemented together. © Copyright NewPath Learning. All Rights Reserved. 94-4669 Visit www.newpathlearning.com for Online Learning Resources.
classified into Pause and Review Complete the concept map to illustrate the difference between rocks and minerals. What are they made of? How are they formed? © Copyright NewPath Learning. All Rights Reserved. 94-4669 Visit www.newpathlearning.com for Online Learning Resources. What is a Rock? Rocks Minerals must meet four criteria are made of