A cameo portrait of Nero is set in the right-hand side of the removable trapezoidal panel on the front of the shrine. It is the same shape and size as the Venus intaglio. Together with the Ptolemy Cameo, which was stolen in 1574, these three major ancient gems constituted a major focus of attention on the front of the shrine. It is possible that they were a reference to the skulls of the three Magi that were visible when the trapezoidal panel was removed. The theme of Agrippina’s coronation of Nero (she can be seen holding a laurel wreath over his head) may have been re-interpreted in the context of the medieval interpretation that biblical kings were the predecessors of German rulers.
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