Sample 80MW0014 is a banded orthogneiss composed of
K-feldspar (50%), quartz (30%), plagioclase (17%), chlorite (2%), oxides
(1%), and trace garnet, biotite and muscovite. Porphyroclasts of both
plagioclase and K-feldspar reach lengths of 10mm. Elongated, perthitic
K-feldspar grains are aligned in the foliation. Plagioclase is in some
cases heavily altered and possibly antiperthitic. The garnet appears to
be metamorphic, and may suggest lower amphibolite facies conditions.
Nearly all biotite is altered to chlorite.