"Vormals" is German for "formerly", your Swaty is saying "formerly of Marburg". I'm not clear where exactly it fits in the lineage but it's definitely later on. If I understand correctly, Swaty was originally in Wahring, Austria. Then Marburg, Austria. Apparently Marburg became part of Yugoslvia and that's when you started having the Yugoslavian Swaty's. Maribor is the same place as Marburg, just in Yugoslavian as opposed to in German.
I've read that some people test their Barber hones, trying them after certain stones and then examining the edge under magnification to see if the edge is improved or worsened.