In The North Nopah


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This comment is from R.C., a practicing geologist who taught me never to say granite unless I was absolutely certain, true granite relatively uncommon. Best to say something is granitic. Hi Tom, You have a granitic porphyry. The pink rectangles are large crystals of feldspar that formed at depth. It’s the first mineral to crystallize. Then the magma was moved closer to the surface, cooled more rapidly, so the other minerals didn’t have time to form very large crystals. The pink feldspar crystals are phenocrysts, from Greek for “visible crystals.” Neat rock. #geology#granite #nopahrangewilderness #inyocounty#rockhounding#geologistonboard#feldspar#minerals

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About thomasfarley01

Freelance writer specializing in outdoor subjects, particularly rocks, gems and minerals.
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