The top 10 marbles from the run must be killers. And I do see that type of indentation (fine cold rolling) on a lot of "spun" marbles, vintage and new. I think "Superman" just references the color combination not a particular marble type. There are Akro, Alley, and Peltier Supermans, right? Don't know that I have ever seen or heard of a Vitro Superman. And although I may have seen Multicolor Swirls with superman colors, I am unlikely to mistake them for these, that's for sure.