2012 – ALTA 2012, Perth WA
The Paulsens gold deposit in the Pilbara region of Western Australia was discovered by CRA in 1998. In
2001, St Barbara Mines Limited (St Barbara) made a successful takeover offer for Taipan Resources NL and
then began an update of the previous Bankable Feasibility Study (BFS) undertaken by Minproc Limited.
This paper describes the history of the metallurgical testwork, plant design and initial development to
optimise a project with complex metallurgical process characteristics and manage the risks.
The Paulsens ore is preg robbing, has cyanide soluble copper and nickel and is highly sulphidic. The ore is
relatively hard and requires a very fine grind size of P80 53 microns. The metallurgical challenges have been
met for this complex ore and the process flowsheet included aspects not commonly associated with a typical
Geometallurgical mapping of the global ore body to understand the variability of cyanide soluble copper and
nickel as well as potential problems from preg robbing waste was undertaken to assess the risks and
suitability of the proposed flowsheet. Concurrently, the mine schedule could be optimised to manage the
levels of copper and nickel in the feed by understanding the copper behaviour with respect to block