What are rocks made of? Minerals are not made by people; they are … …naturally occurring substances. Name four properties (or clues) that scientists use to identify minerals. Color, luster, streak, and hardness Which property means the way the light bounces off the mineral? What words can be used to describe a mineral’s luster? Glassy, dull, shiny, greasy Why is color not a good property to use to identify a mineral? slate limestone Many minerals have the same color. What are three testers that can be used to determine a mineral’s hardness? fingernail, penny, nail What type of rock is formed when magma cools and hardens? What type of rock is formed when change occurs from heat and pressure in the Earth? What type of rock is formed when weathering and erosion cause sediments to press together in layers? Melted rock below the Earth’s surface is called… Small bits and pieces of rocks are called… The breaking down and wearing away of rocks is called… The movement of sediments from one place to another is called… What is any trace, mark, or remains of an organism called? How old must a fossil be? Now that’s old!! 10,000 years What kind of rock are fossils usually preserved in? They study Why do them to scientists learn about study fossils? extinct plants and animals.