An augen orthogneiss, sample 27MW0102 consists of
K-feldspar (40%), plagioclase (31%), quartz (25%), biotite (2%), and
trace amounts of muscovite, sphene, epidote, chlorite, and oxides.
Grains of plagioclase are entirely recrystallized, while K-feldspar
porphyroclasts are in tact and wrapped by biotite. A foliation is
defined by biotite and elongated aggregates of quartz and plagioclase.