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GABBRO   (detail)

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Typical Minerals
Ca PLAGIOCLASE & MAFICS (pyroxene) about 50/50

Amphibole often present
Olivine - absent to trace
Detail Description
     In this detail we see the mixed pyroxene and light gray calcium-rich plagioclase.
     In a color/texture classification we expect gabbro to be a dark rock, but what is crucial is the presence of pyroxene, seen here as black, irregular fractured masses.
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Last Update: 9/29/00

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