Biotite in thin section

My ADHD is forcing me to keep posting these biotites, so I am opening a 3ad. I am sorry! All pics are 3 mm wide.

#ThinSectionThursday #geology #structuralgeology #micafish #mylonite
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Biotite fish in mylonitic granite.
Island of Elba, Italy

FOV 3 mm

#geology #thinsection #granite #mylonite #micafish #biotite

biotite 'mica fish'

This one changed my day for the better!

#micafish #mylonite #geology
CPL 3 mm

Biotite (brown) replaced by chlorite (blue) in a mylonitic granite

How to make both Tectonics & Petrology folks happy!

Biotite #micafish replaced by chlorite

#mylonite #geology
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