I am in the middle of cleaning up the Dilecta I purchased at T-town this year and discovered something about polishing aluminum hammered or smooth fenders.
The fenders on this bike are combination hammered edges with smooth center with a frame colored matched stripe on either side. I typically use Turtle Wax rubbing compound to bring out tired paint and it does a great job if you are careful on how much you work it.
I used it on that colored stripe on the fender and when I cleaned the compound off I noticed the aluminum area around the strip was now clean and shining like a mirror. I have seen aluminum polished up mirror like before and always wondered how it was done. I then took more rubbing compound and began to polish the bare aluminum and darned if these fenders, hammered section and all, did not come out looking almost new. It is great when you find a new application for an old product. Tried a bit on the Stronglight cranks and TA rings and again fantastic results. Now I can address the white haze (aluminum oxide) when ever it shows up on a bike.