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How can I tell if a rock is metamorphic or sedimentary?
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Metamorphic rocks are formed when existing rocks are subjected to extreme heat and pressure. Sedimentary rocks are formed by the accumulation of particles over time, usually in an aquatic environment. You can often tell the difference between these two types of rocks by looking at their physical characteristics. Metamorphic rocks will often have a distinct grainy texture, while sedimentary rocks may be more homogeneous and smooth. Additionally, metamorphic rocks tend to have different minerals than sedimentary rocks, as well as a higher concentration of quartz crystals.