You can polish it as I do. I don't like ugly props on my boats. The people that don't brighten them up only gain just a little more speed, insignificant to the rest of us that don't want that 1/100th MPH. Besides, it is one of the few things that my son will do on the boats. He tells me that he is working on his own "secret" formula for prop polish.
Some people try to get overly technical with their props like trying to index them.