Firstly, it is a rare example of ancient sculpture that retains the extremely realistic eyes of the original. Ancient sculpture was commonly painted, but almost always this decoration has worn off, giving us moderns a very different vision to what the original audience must have seen. The head of Meroe has been preserved.
Secondly, it is a reminder of how politicised these statues could be. Augustus sent this sort of stock image all over the Empire, as a reminder of how important he was. The Africans who hacked it off buried it under the entrance of a building so that they could ritually walk over the might of Rome on a regular basis. The exhibition runs to 15 February.