Rod of Rassilon

The Rod of Rassilon was one of the artefacts of Rassilon. Together with the Sash of Rassilon, it could be used to raise the control structure for the Eye of Harmony located beneath the Panopticon on Gallifrey.

The Rod slots into the control structure (a black obelisk), allowing the person wielding it (wearing the Sash of Rassilon) to disengage the control interfaces and gain access to the power of the Eye of Harmony. (DW: The Deadly Assassin)

The Rod is also given as part of the Sash of Rassilon and the Coronet of Rassilon to Presidents upon being made Lord President of Gallifrey. (DW: The Invasion of Time)