A couple of people (Letitia and Tim B.) posted these pics on facebook and I loved the simlarity yet difference.
West Virginia swirls versus Jabos. The swirls ribbons happen to fluoresce. Don't yet know if that is significant.
So this hopefully shows how it's at least a little bit easier to identify the opaque glass as a "ribbon" and the transparent glass as the "base" in the WV swirl, while in the Jabo it's harder to pick out which glass would be the ribbon and which glass would be the base.