Pretend you're a geologist classifying rocks. How would you classifying them? What would you use? Well, most geologist use there eyes and other tools to do the job. Most Geologists observe the rocks Mineral Composition, color and texture. Classifying rocks is also a way to tell one rock from another. Lets say there are two rocks in front of you, they look exactly the same. One of the rocks is a Sedimentary rock. The other is a Metamorphic. How would you tell them apart? Well, that's why we classify rocks, to tell them apart from each other. Mineral Composition, is the rock. Not the rock itself, but the what is the rock made of,. rocks usually always have minerals in them. Granite is a light colored rock, it has four types of minerals in it. Quartz, Feldspar, Hornblende, and Mica. Color, another way to classify rocks is a very simple way of classifying. Just use you eyes. Color also gives us clues to the rock's Mineral Composition. Texture, is how the mineral feels or looks. To determine a rocks texture geologists use terms based on the rock's shape, size and pattern.
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