Ann: Results from Rosie Prospect , page-22

If you look at the bottom of the news releases from STB it usually says this :

About the Joint Venture
In early 2004, South Boulder entered a farm-out Joint Venture (JV) Agreement with
Independence, whereby Independence can earn a 70% interest in the nickel rights
on tenements held by South Boulder in the Duketon Project, by the completion of a
Bankable Feasibility Study within 5 years. The data, interpretation, cross and long
section diagrams that form this ASX release have been provided courtesy of
Independence.

As it mentions that IGO earn 70% of the nickel rights and omits any mention of the PGE rights my inference is that STB retain 100% of all other minerals (including gold, platinum, copper etc).