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In the week one lab, members of the class were to classify six unknown rocks into one of the three rock types: igneous, sedimentary, and metamorphic. We were then to use that knowledge, along with other features of the rocks, to determine the rock name. This paper will identify each of the six samples based off the observations of each sample in the lab. The paper will go on to discuss the main properties of igneous, sedimentary and metamorphic rock. This paper will conclude with a discussion on what classification of a rock is the most useful in determining the name of the rock.
Rock A - Marble Rock sample A is marble. “Marble is a metamorphic rock that forms when limestone is subjected to the heat and pressure of metamorphism” (King, 2013). This particular sample is white in color and contains medium, coarse grains. The grains are visible and are easy to feel when picking up the rock and moving it between around in my hands. Marble has many uses in architecture and sculpture making it a popular material for these applications.
Rock B - Gneiss Rock sample B is gneiss. This sample was easy to identify based on the obvious banding throughout the layers of the sample. Gneiss is another metamorphic rock that originally was an igneous rock, granite. Through the process of metamorphism, the heat and pressures associated with the process may have caused the layers of mineral grains to flatten. “Gneiss displays distinct alternating layers composed of different minerals. Gneiss does not break along planes of foliation because less than 50% of the minerals formed during the metamorphism are aligned in thin layers” (UA, 2005). A visual inspection of the rock shows the quartz and feldspar composition within the layers of the sample.
Rock C - Limestone Rock sample C is limestone. Limestone is “organic sedimentary rock that forms from the accumulation

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