Some sources say it's some form of a red and blue striped tie.
superman.nu/forum/reply.php?id=33,33
ournextspeaker.com/uploaded_images/IntegrityTheClarkKentEffect_131FC/Clark_Kent.jpg
meaa.aesthetiques.org/images/clarkkent1.jpg
centurysendsavior.com/images/ClarkKentHT63.jpg
[these four webpages no longer exist]
His tie in this comic does appear brown:
supermanartists.comics.org/superwhoswho/antii-supermangang-Superman133-18.jpg
[no longer exists]
In this clip it's silver and blue:
http://www.youtube.com/watch?v=9djfa9CIm3M&feature=related
In this clip it's plata and Azul (silver and blue):
http://www.youtube.com/watch?v=-s04eIM1joY&feature=related
Other scenes in Superman II it's red and blue.
