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A More Detailed Look
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| PLAGIOGRANITE (detail)
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Return to Whole Image A More Detailed Look Return to Classification; pdf version
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Typical Minerals QUARTZ > 20% PLAGIOCLASE is greater than Orthoclase (may be absent all together) Mafics - < 10% |
Detail Description
In this greater detail we see the mixed clear to translucent light colored sodium plagioclase and quartz (still hard to separate in a photograph.) Orthoclase is notably absent. The mafic (black) minerals are still not easily identified even under this magnification. We need to be able to rotate the specimen under a microscope looking for the cleavages to be sure of identification. |
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| Last Update: 9/29/00 | e-mail: (Fichtels@jmu.edu) |