Category:Porphyritic igneous rocks in the United States

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Media in category "Porphyritic igneous rocks in the United States"

The following 2 files are in this category, out of 2 total.

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  Porphyritic diabase (Cape Ann, Massachusetts, USA) 3.jpg 3,273 × 2,625; 6.24 MB
  
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  Porphyritic diabase (Cape Ann, Massachusetts, USA) 6.jpg 3,993 × 2,186; 6.77 MB