Looking into wikipedia trying to follow the coats of arms of Saxony I found a coat of arms that could represent the second shield. It is made of two sword crossed. “The lower right fourth quarter shows in sable and argent the electoral swords (Kurschwerter) in gules, indicating the Saxon office as Imperial Arch-Marshal (German:Erzmarschall, Latin:Archimarescallus), pertaining to the Saxon privilege as prince-elector, besides the right to elect a new emperor after the decease of the former. The Lauenburg branch duchy adopted this coat-of-arms, used before by the other brach duchy Saxe-Wittenberg until its extinction in 1422, in order to enforce its failed claim to succession in Saxe-Wittenberg.”
http://en.wikipedia.org/wiki/File:Sachsen-Lauenburg.PNG