What is REX's worth

With the uncertainty of REX's future over the last couple of years the share price drifted to unbelievable lows. In earlier discussions they compared REX to Sandfire , OZL Prominent Mine as slightly better and longer lasting mines and those two are valued over the Billion dollar mark. With all obstacles cleared and the greenlight towards production its hard to put a finger on its worth. All I know is that the potential is there and when will the investors realise its true value.
Its nice to see the stock starting to move In the right direction now anyway. Its been a long time for everyone since the initial strike.