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PLAGIOGRANITE   (detail)

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A More Detailed Look

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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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