Looks and sounds like the bike is pretty much original. I believe those were originally equipped with Weimann alloy rims.

My wife's 80s Schwinn World (made by Giant) has a set of Rigida steel rims, and although they are in great shape, they are heavy. Seems like steel looks very 'chromy' like the chrome part of the fork, but alloy is less shiny and reflective. Hard to tell from the photos.

Love that shade of yellow!