Types of Rocks and minerals
A mineral is a solid that has formed naturally and is made of definite crystal shape. Scientist classify minerals using five different methods. Cleavage is when rocks split where it is smooth and flat. Luster is the reflection of light off the rocks surface. Fracture is when a rock breaks unevenly. Streak is the mark it leaves when rubbed on a streak plate. Lastly scientists classify minerals by the color of the rock. There are three types of lusters metallic, submetallic, and nonmetallic. Metallic is shiny. The submetallic and nonmetallic luster are dull. To test a minerals hardness people use the Mohs hardness scale, it tests a rocks resistant to being scratched.
There are three types of rocks Igneous, Metamorphic, and Sedimentary rocks. Igneous forms when magma cools and solidifies. Th magma solidifies between 700 and 1,250C. There are two types of igneous rocks course grained and fine grained. The difference between them is how long it takes for the magma to cool. The longer it takes to cool the more crystals there are and larger they are. The second rock is the Sedimentary rock. The sedimentary rock is categorized as a few different rocks like conglomerate, sandstone, siltstone, and shale. When pieces of rock break off from weathering and form into compacted layers is what sedimentary rocks are. One interesting thing about sedimentary rocks is that they have lots of layers. Lastly the third rock is metamorphic rocks which is when rocks with structure, texture, and the composition of a rock has changed. When the environment of the rock changes the rock goes through metamorphism which is the changing of rocks. Metamorphism occurs when inside the Earth's crust the temperature and pressure changes. All three rocks are related in different ways.These are just some of the things about the three major types of rocks.
Information from: Holt Science and Technology Earth Science text book
Pictures from: http://www.indiana.edu/~geol116/week6/metarx.jpg, http://www.indiana.edu/~geol116/Week5/sedrocks.jpg, and http://www.rocksmineralscollections.com/products/collection-of-igneous-rocks.jpg and http://03.edu-cdn.com/files/static/wiley/9780471148029/TRANSFORMED_03.GIF
There are three types of rocks Igneous, Metamorphic, and Sedimentary rocks. Igneous forms when magma cools and solidifies. Th magma solidifies between 700 and 1,250C. There are two types of igneous rocks course grained and fine grained. The difference between them is how long it takes for the magma to cool. The longer it takes to cool the more crystals there are and larger they are. The second rock is the Sedimentary rock. The sedimentary rock is categorized as a few different rocks like conglomerate, sandstone, siltstone, and shale. When pieces of rock break off from weathering and form into compacted layers is what sedimentary rocks are. One interesting thing about sedimentary rocks is that they have lots of layers. Lastly the third rock is metamorphic rocks which is when rocks with structure, texture, and the composition of a rock has changed. When the environment of the rock changes the rock goes through metamorphism which is the changing of rocks. Metamorphism occurs when inside the Earth's crust the temperature and pressure changes. All three rocks are related in different ways.These are just some of the things about the three major types of rocks.
Information from: Holt Science and Technology Earth Science text book
Pictures from: http://www.indiana.edu/~geol116/week6/metarx.jpg, http://www.indiana.edu/~geol116/Week5/sedrocks.jpg, and http://www.rocksmineralscollections.com/products/collection-of-igneous-rocks.jpg and http://03.edu-cdn.com/files/static/wiley/9780471148029/TRANSFORMED_03.GIF