I don't think Clemens would have purposely mislead on his passport
applications. That eye color may be just the way he perceived himself when
he looked in a mirror. (Eye pigments in the iris compress or spread apart
when the pupil changes, sometimes changing the eye color a bit. Certain
emotions also can change both pupil size and iris color.) On p. 105 of the
UCal edition of FAMILY SKETCH, Susy describes her father as having "kind
blue eyes." In spite of a possible self-image of having "gray eyes", the
historical "eye witnesses" say otherwise.
Barb